Professor Ben Murdin

Research Interests

I am an experimentalist interested in the study of electronic and optical properties of semiconductors and semiconductor nanostructures using high-pressures, magnetic-fields, and linear, nonlinear and time resolved infrared spectroscopy. I am a regular user of the Free-Electron Laser, FELIX, in Holland, and I am the coordinator and spokesperson for UK Condensed Matter Physics users there. I am also a Programme Advisory Committee member for the Dresden laser, FELBE.  I like "applicable physics" rather than really pure or really applied physics, for example I study how quickly and why electron spins lose their memory (applicable to spintronic devices). I chaired the International Conference on Narrow Gap Semiconductors, here in Guildford in 2007.

Research Collaborations

I have strong research links with the groups of Prof. Carl Pidgeon (my best friend and mentor) at Heriot-Watt University, Prof Gabriel Aeppli at UCL, Prof. Wolfgang Heiss at Uni. Linz, Dr Lesley Cohen at Imperial College London, Dr Tony Krier at Lancaster, Dr Tim Ashley at QinetiQ Ltd and Dr Lex van der Meer at the Free Electron Laser in Utrecht.

Further details can be found on my personal web page.

A full list of publications, conference presentations, and patents can be found here.

Teaching

In the Physics Department I teach level one Data Handling (aka probability and statistics), level two physics laboratory, level three Physics of Stars. On the MSc in Medical Physics I teach Medical Statistics. For EE I teach a component of the MSc module Nanoelectronics and Devices on spintronics.

Departmental Duties

I manage the department's final year projects, and I am the course coordinator for the Physics with Satellite Technology degree pathway. I am chair of the Physics department's equality and diversity committee and am an External Examiner for the Physics Department at Heriot-Watt University.

Contact Me

E-mail:
Phone: 01483 68 9328

Find me on campus
Room: 15 ATI 01

Publications

Highlights

• . (2015) 'Optical pumping and readout of bismuth hyperfine states in silicon for atomic clock applications.'. Sci Rep, England: 5

Abstract

The push for a semiconductor-based quantum information technology has renewed interest in the spin states and optical transitions of shallow donors in silicon, including the donor bound exciton transitions in the near-infrared and the Rydberg, or hydrogenic, transitions in the mid-infrared. The deepest group V donor in silicon, bismuth, has a large zero-field ground state hyperfine splitting, comparable to that of rubidium, upon which the now-ubiquitous rubidium atomic clock time standard is based. Here we show that the ground state hyperfine populations of bismuth can be read out using the mid-infrared Rydberg transitions, analogous to the optical readout of the rubidium ground state populations upon which rubidium clock technology is based. We further use these transitions to demonstrate strong population pumping by resonant excitation of the bound exciton transitions, suggesting several possible approaches to a solid-state atomic clock using bismuth in silicon, or eventually in enriched (28)Si.

• . (2015) 'Coherent creation and destruction of orbital wavepackets in Si:P with electrical and optical read-out'. Nature Communications, 6

Abstract

© 2015 Macmillan Publishers Limited. All rights reserved.The ability to control dynamics of quantum states by optical interference, and subsequent electrical read-out, is crucial for solid state quantum technologies. Ramsey interference has been successfully observed for spins in silicon and nitrogen vacancy centres in diamond, and for orbital motion in InAs quantum dots. Here we demonstrate terahertz optical excitation, manipulation and destruction via Ramsey interference of orbital wavepackets in Si:P with electrical read-out. We show milliradian control over the wavefunction phase for the two-level system formed by the 1s and 2p states. The results have been verified by all-optical echo detection methods, sensitive only to coherent excitations in the sample. The experiments open a route to exploitation of donors in silicon for atom trap physics, with concomitant potential for quantum computing schemes, which rely on orbital superpositions to, for example, gate the magnetic exchange interactions between impurities.

• . (2014) 'High-field impurity magneto-optics of Si:Se'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 90 (11) Article number ARTN 115204
• . (2014) 'Photon assisted tunneling in pairs of silicon donors'. Physical Review B - Condensed Matter and Materials Physics, 89 (23)

Abstract

Shallow donors in silicon are favorable candidates for the implementation of solid-state quantum computer architectures because of the promising combination of atomiclike coherence properties and scalability from the semiconductor manufacturing industry. Quantum processing schemes require (among other things) controlled information transfer for readout. Here we demonstrate controlled electron tunneling at 10 K from P to Sb impurities and vice versa with the assistance of resonant terahertz photons. © 2014 American Physical Society.

• . (2014) 'Picosecond dynamics of a silicon donor based terahertz detector device'. Applied Physics Letters, 105 (2)

Abstract

We report the characteristics of a simple complementary metal-oxide-semiconductor compatible terahertz detector device with low response time (nanoseconds) determined using a short-pulse, high intensity free-electron laser. The noise equivalent power was 1 × 10-11 W Hz -1/2. The detector has an enhanced response over narrow bands, most notably at 9.5 THz, with a continuum response at higher frequencies. Using such a device, the dynamics of donors in silicon can be explored, a system which has great potential for quantum information processing. © 2014 AIP Publishing LLC.

• . (2013) 'Isotope effect on the lifetime of the 2p(0) state in phosphorus-doped silicon'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 88 (3) Article number ARTN 035201
• . (2013) 'Si:P as a laboratory analogue for hydrogen on high magnetic field white dwarf stars.'. Nature Publishing Group Nat Commun, England: 4

Abstract

Laboratory spectroscopy of atomic hydrogen in a magnetic flux density of 10(5) T (1 gigagauss), the maximum observed on high-field magnetic white dwarfs, is impossible because practically available fields are about a thousand times less. In this regime, the cyclotron and binding energies become equal. Here we demonstrate Lyman series spectra for phosphorus impurities in silicon up to the equivalent field, which is scaled to 32.8 T by the effective mass and dielectric constant. The spectra reproduce the high-field theory for free hydrogen, with quadratic Zeeman splitting and strong mixing of spherical harmonics. They show the way for experiments on He and H(2) analogues, and for investigation of He(2), a bound molecule predicted under extreme field conditions.

• . (2010) 'Coherent control of Rydberg states in silicon'. NATURE PUBLISHING GROUP NATURE, 465 (7301), pp. 1057-U116.
• . (2010) 'Strong dependence of spin dynamics on the orientation of an external magnetic field for InSb and InAs'. AMER INST PHYSICS APPLIED PHYSICS LETTERS, 96 (11) Article number ARTN 111107
• . (2009) 'Continuous Voltage Tunability of Intersubband Relaxation Times in Coupled SiGe Quantum Well Structures Using Ultrafast Spectroscopy'. AMER PHYSICAL SOC PHYSICAL REVIEW LETTERS, 102 (14) Article number ARTN 147401
• . (2008) 'Silicon as a model ion trap: Time domain measurements of donor Rydberg states'. NATL ACAD SCIENCES PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 105 (31), pp. 10649-10653.
• . (2008) 'Temperature dependence of the electron Lande g factor in InSb and GaAs'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 77 (3) Article number ARTN 033204

Journal articles

• . (2017) 'Competition between homogeneous and inhomogeneous broadening of orbital transitions in Si:Bi'. American Physical Society Physical Review B, 96 (15) Article number 155204 , pp. 1-8.

Abstract

We present results for the lifetime of the orbital transitions of Bi donors in Si, measured using both frequency domain and time-domain techniques, allowing us to distinguish between homogeneous and inhomogeneous processes. The proximity of the energy of the optically allowed transitions to the optical phonon energy means that there is an unusually wide variation in the lifetimes and broadening mechanisms for this impurity, from fully homogeneous lifetime-broadened transitions to fully inhomogeneously broadened lines. The relaxation lifetime (T1) of the states range from the low 10’s to 100’s of ps, and we find that there is little extra dephasing (so that T1 is of the order of T2/2) in each case.

• . (2017) 'Coherent superpositions of three states for phosphorous donors in silicon prepared using THz radiation'. Nature Publishing Group Nature Communications, 8 Article number 16038

Abstract

Superposition of orbital eigenstates is crucial to quantum technology utilising atoms, such as atomic clocks and quantum computers, and control over the interaction between atoms and their neighbours is an essential ingredient for both gating and readout. The simplest coherent wavefunction control uses a 2-eigenstate admixture, but more control over the spatial distribution of the wavefunction can be obained by increasing the number of states in the wavepacket. Here we demonstrate THz laser pulse control of Si:P orbitals using multiple orbital state admixtures, observing beat patterns produced by Zeeman splitting. The beats are an observable signature of the ability to control the path of the electron, which implies we can now control the strength and duration of the interaction of the atom with different neighbours. This could simplify surface code networks which require spatially controlled interaction between atoms, and we propose an architecture that might take advantage of this.

• . (2017) 'Observation of a different birefringence order at optical and THz frequencies in LBO crystal'. Elsevier Optical Materials, 66, pp. 94-97.

Abstract

THz optical properties of lithium borate (LBO) crystals were measured using time-domain spectroscopy (TDS). The LBO crystal samples were of high optical quality and were cut and polished along the h100i, h010i and h001i axes. Two independent measurements were performed in order to con rm the reproducibility and consistency of results. The contradictions in the previously published data on the THz optical properties of LBO were clari ed. It was shown that the birefringence order at THz frequencies is nz < nx < ny, whereas at optical frequencies it is known to be nx < ny < nz. It was seen that nz, which has the highest value in the visible, has the lowest value at THz. This is explained in terms of ionic polarizability and is consistent with the fact that the THz absorption coe cient for a wave polarized along the Z-axis is more than an order of magnitude lower than for the X and Y axes. Absorption as low as 0.2 cm 1 was found at frequencies up to 0.5 THz for a wave polarized parallel to the Z-axis. A set of new dispersion equations was designed for the entire transparency range.

• . (2016) 'Weak probe readout of coherent impurity orbital superpositions in silicon'. American Physical Society Physical Review B - Condensed Matter and Materials Physics, 94 (23) Article number 235207

Abstract

Pump-probe spectroscopy is the most common time-resolved technique for investigation of electronic dynamics, and the results provide the incoherent population decay time T1. Here we use a modified pump-probe experiment to investigate coherent dynamics, and we demonstrate this with a measurement of the inhomogeneous dephasing time T2* for phosphorus impurities in silicon. The pulse sequence produces the same information as previous coherent all-optical (photon-echo-based) techniques but is simpler. The probe signal strength is first order in pulse area but its effect on the target state is only second order, meaning that it does not demolish the quantum information. We propose simple extensions to the technique to measure the homogeneous dephasing time T2, or to perform tomography of the target qubit.

• . (2016) 'The Quadratic Zeeman effect used for state-radius determination in neutral donors and donor bound excitons in Si:P'. IOP Semiconductor Science and Technology, 31 Article number 045007 , pp. 045007-045007.

Abstract

We have measured the near-infrared photoluminescence spectrum of phosphorus doped silicon (Si: P) and extracted the donor-bound exciton (D0X) energy at magnetic fields up to 28 T. At high field the Zeeman effect is strongly nonlinear because of the diamagnetic shift, also known as the quadratic Zeeman effect (QZE). The magnitude of the QZE is determined by the spatial extent of the wave-function. High field data allows us to extract values for the radius of the neutral donor (D0) ground state, and the light and heavy hole D0X states, all with more than an order of magnitude better precision than previous work. Good agreement was found between the experimental state radius and an effective mass model for D0. The D0X results are much more surprising, and the radius of the mJ=±3/2 heavy hole is found to be larger than that of the mJ=±1/2 light hole.

• . (2015) 'Quantitative analysis of electrically detected Ramsey fringes in P-doped Si'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 92 (16) Article number ARTN 165310
• . (2015) 'Nano-orbitronics in silicon'. Springer Proceedings in Physics, 159, pp. 92-93.
• . (2015) 'Optical pumping and readout of bismuth hyperfine states in silicon for atomic clock applications.'. Sci Rep, England: 5

Abstract

The push for a semiconductor-based quantum information technology has renewed interest in the spin states and optical transitions of shallow donors in silicon, including the donor bound exciton transitions in the near-infrared and the Rydberg, or hydrogenic, transitions in the mid-infrared. The deepest group V donor in silicon, bismuth, has a large zero-field ground state hyperfine splitting, comparable to that of rubidium, upon which the now-ubiquitous rubidium atomic clock time standard is based. Here we show that the ground state hyperfine populations of bismuth can be read out using the mid-infrared Rydberg transitions, analogous to the optical readout of the rubidium ground state populations upon which rubidium clock technology is based. We further use these transitions to demonstrate strong population pumping by resonant excitation of the bound exciton transitions, suggesting several possible approaches to a solid-state atomic clock using bismuth in silicon, or eventually in enriched (28)Si.

• . (2015) 'Coherent creation and destruction of orbital wavepackets in Si:P with electrical and optical read-out'. Nature Communications, 6

Abstract

© 2015 Macmillan Publishers Limited. All rights reserved.The ability to control dynamics of quantum states by optical interference, and subsequent electrical read-out, is crucial for solid state quantum technologies. Ramsey interference has been successfully observed for spins in silicon and nitrogen vacancy centres in diamond, and for orbital motion in InAs quantum dots. Here we demonstrate terahertz optical excitation, manipulation and destruction via Ramsey interference of orbital wavepackets in Si:P with electrical read-out. We show milliradian control over the wavefunction phase for the two-level system formed by the 1s and 2p states. The results have been verified by all-optical echo detection methods, sensitive only to coherent excitations in the sample. The experiments open a route to exploitation of donors in silicon for atom trap physics, with concomitant potential for quantum computing schemes, which rely on orbital superpositions to, for example, gate the magnetic exchange interactions between impurities.

• . (2014) 'Crystal field analysis of Dy and Tm implanted silicon for photonic and quantum technologies'. Optics Express, 22 (24), pp. 29292-29303.

Abstract

© 2014 Optical Society of America.We report the lattice site and symmetry of optically active Dy3+ and Tm3+ implanted Si. Local symmetry was determined by fitting crystal field parameters (CFPs), corresponding to various common symmetries, to the ground state splitting determined by photoluminescence measurements. These CFP values were then used to calculate the splitting of every J manifold. We find that both Dy and Tm ions are in a Si substitution site with local tetragonal symmetry. Knowledge of rare-earth ion symmetry is important in maximising the number of optically active centres and for quantum technology applications where local symmetry can be used to control decoherence.

• . (2014) 'High-field impurity magneto-optics of Si:Se'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 90 (11) Article number ARTN 115204
• . (2014) 'Photon assisted tunneling in pairs of silicon donors'. Physical Review B - Condensed Matter and Materials Physics, 89 (23)

Abstract

Shallow donors in silicon are favorable candidates for the implementation of solid-state quantum computer architectures because of the promising combination of atomiclike coherence properties and scalability from the semiconductor manufacturing industry. Quantum processing schemes require (among other things) controlled information transfer for readout. Here we demonstrate controlled electron tunneling at 10 K from P to Sb impurities and vice versa with the assistance of resonant terahertz photons. © 2014 American Physical Society.

• . (2014) 'Picosecond dynamics of a silicon donor based terahertz detector device'. Applied Physics Letters, 105 (2)

Abstract

We report the characteristics of a simple complementary metal-oxide-semiconductor compatible terahertz detector device with low response time (nanoseconds) determined using a short-pulse, high intensity free-electron laser. The noise equivalent power was 1 × 10-11 W Hz -1/2. The detector has an enhanced response over narrow bands, most notably at 9.5 THz, with a continuum response at higher frequencies. Using such a device, the dynamics of donors in silicon can be explored, a system which has great potential for quantum information processing. © 2014 AIP Publishing LLC.

• . (2013) 'Isotope effect on the lifetime of the 2p(0) state in phosphorus-doped silicon'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 88 (3) Article number ARTN 035201
• . (2013) 'Quantum Computing from the Ground Up'. TAYLOR & FRANCIS LTD CONTEMPORARY PHYSICS, 54 (2), pp. 116-117.
• . (2013) 'Semiconductor Spintronics'. TAYLOR & FRANCIS LTD CONTEMPORARY PHYSICS, 54 (2), pp. 118-119.
• . (2013) 'Time-Resolved Dynamics of Shallow Acceptor Transitions in Silicon'. AMER PHYSICAL SOC PHYSICAL REVIEW X, 3 (1) Article number ARTN 011019
• . (2013) 'Si:P as a laboratory analogue for hydrogen on high magnetic field white dwarf stars.'. Nature Publishing Group Nat Commun, England: 4

Abstract

Laboratory spectroscopy of atomic hydrogen in a magnetic flux density of 10(5) T (1 gigagauss), the maximum observed on high-field magnetic white dwarfs, is impossible because practically available fields are about a thousand times less. In this regime, the cyclotron and binding energies become equal. Here we demonstrate Lyman series spectra for phosphorus impurities in silicon up to the equivalent field, which is scaled to 32.8 T by the effective mass and dielectric constant. The spectra reproduce the high-field theory for free hydrogen, with quadratic Zeeman splitting and strong mixing of spherical harmonics. They show the way for experiments on He and H(2) analogues, and for investigation of He(2), a bound molecule predicted under extreme field conditions.

• . (2012) 'Quantum control in silicon using coherent THz pulses'. Proceedings of SPIE - The International Society for Optical Engineering, 8496
• . (2011) 'Experimental determination of the Rashba coefficient in InSb/InAlSb quantum wells at zero magnetic field and elevated temperatures'. IOP PUBLISHING LTD JOURNAL OF PHYSICS-CONDENSED MATTER, 23 (3) Article number ARTN 035801
• . (2010) 'Coherent control of Rydberg states in silicon'. NATURE PUBLISHING GROUP NATURE, 465 (7301), pp. 1057-U116.
• . (2010) 'Strong dependence of spin dynamics on the orientation of an external magnetic field for InSb and InAs'. AMER INST PHYSICS APPLIED PHYSICS LETTERS, 96 (11) Article number ARTN 111107
• . (2010) 'Circular photogalvanic effect in HgTe/CdHgTe quantum well structures'. IOP PUBLISHING LTD SEMICONDUCTOR SCIENCE AND TECHNOLOGY, 25 (9) Article number ARTN 095005
• . (2010) 'Quantum control of phosphorus donor rydberg states in silicon'. IEEE International Conference on Group IV Photonics GFP, , pp. 380-382.
• . (2009) 'Gain recovery dynamics of a terahertz quantum cascade laser'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 80 (7) Article number ARTN 075303
• . (2009) 'Continuous Voltage Tunability of Intersubband Relaxation Times in Coupled SiGe Quantum Well Structures Using Ultrafast Spectroscopy'. AMER PHYSICAL SOC PHYSICAL REVIEW LETTERS, 102 (14) Article number ARTN 147401
• . (2009) 'Far-infrared free-electron lasers and their applications'. TAYLOR & FRANCIS LTD CONTEMPORARY PHYSICS, 50 (2) Article number PII 910353824 , pp. 391-406.
• . (2009) 'Fast detector of the ellipticity of infrared and terahertz radiation based on HgTe quantum well structures'. AMER INST PHYSICS JOURNAL OF APPLIED PHYSICS, 105 (1) Article number ARTN 013106
• . (2008) 'Temperature dependence of the electron spin g factor in GaAs'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 78 (24) Article number ARTN 245203
• . (2008) 'Resonant circular photogalvanic effect in GaN/AlGaN heterojunctions'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 78 (20) Article number ARTN 205435
• . (2008) 'Silicon as a model ion trap: Time domain measurements of donor Rydberg states'. NATL ACAD SCIENCES PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 105 (31), pp. 10649-10653.
• . (2008) 'Zero-field spin splitting and spin lifetime in n-InSb/In(1-x)A1(x)Sb asymmetric quantum well heterostructures (vol 77, art no 165335, 2008)'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 78 (7) Article number ARTN 079901
• . (2008) 'Quantum ratchet effects induced by terahertz radiation in GaN-based two-dimensional structures'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 77 (24) Article number ARTN 245304
• . (2008) 'Zero-field spin splitting and spin lifetime in n-InSb/In1-xAlxSb asymmetric quantum well heterostructures'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 77 (16) Article number ARTN 165335
• . (2008) 'Temperature dependence of the electron Lande g factor in InSb and GaAs'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 77 (3) Article number ARTN 033204
• . (2007) 'Photoluminescence of InNAs alloys: S-shaped temperature dependence and conduction-band nonparabolicity'. AMER PHYSICAL SOC PHYSICAL REVIEW B, 76 (7) Article number ARTN 075209
• . (2007) 'Direct determination of ultrafast intersubband hole relaxation times in voltage biased SiGe quantum wells by a density matrix interpretation of femtosecond resolved photocurrent experiments'. IOP PUBLISHING LTD NEW JOURNAL OF PHYSICS, 9 Article number ARTN 128
• . (2007) 'Interwell relaxation times in p-Si/SiGe asymmetric quantum well structures: Role of interface roughness'. AMERICAN PHYSICAL SOC PHYSICAL REVIEW B, 75 (4) Article number ARTN 045338
• . (2006) 'Spectroscopy of GaAs/AlGaAs quantum-cascade lasers using hydrostatic pressure'. AMER INST PHYSICS APPLIED PHYSICS LETTERS, 89 (22) Article number ARTN 221105
• . (2006) 'Direct monitoring of the excited state population in biased SiGe valence band quantum wells by femtosecond resolved photocurrent experiments'. AMER INST PHYSICS APPLIED PHYSICS LETTERS, 89 (21) Article number ARTN 211111
• . (2006) 'Toward silicon-based lasers for terahertz sources'. IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, 12 (6), pp. 1570-1578.
• . (2006) 'Band anticrossing in GaNxSb1-x'. AMER INST PHYSICS APPLIED PHYSICS LETTERS, 89 (11) Article number ARTN 111921
• . (2006) 'Two- and one-dimensional light propagations and gain in layer-by-layer-deposited colloidal nanocrystal waveguides'. AMER INST PHYSICS APPLIED PHYSICS LETTERS, 89 (11) Article number ARTN 111120
• . (2006) 'Spin lifetime in InAs epitaxial layers grown on GaAs'. AMERICAN PHYSICAL SOC PHYSICAL REVIEW B, 74 (7) Article number ARTN 075331
• . (2006) 'Recombination processes in midinfrared InGaAsSb diode lasers emitting at 2.37 mu m'. AMER INST PHYSICS APPLIED PHYSICS LETTERS, 89 (5) Article number ARTN 051104
• . (2006) 'Spin relaxation in n-InSb/AlInSb quantum wells'. IOP PUBLISHING LTD NEW JOURNAL OF PHYSICS, 8 Article number PII S1367-2630(06)15617-7
• . (2006) 'Spin relaxation by transient monopolar and bipolar optical orientation.'. Phys Rev Lett, United States: 96 (9)
• . (2006) 'Analysis of the major loss processes in mid-infrared type-II "W" diode lasers'. Conference Digest - IEEE International Semiconductor Laser Conference, , pp. 43-44.
• . (2006) 'Band structure and high-pressure measurements'. Springer Series in Optical Sciences, 118, pp. 93-127.
• . (2006) 'Direct measurement of HH2-HH1 intersubband lifetimes in SiGe quantum cascade structures'. Third International SiGe Technology and Device Meeting, ISTDM 2006 - Conference Digest, 2006
• . (2003) 'Spin-galvanic effect due to optical spin orientation'. American Physical Society Physical Review B, 68 (8) Article number 081302 , pp. ---.

Abstract

Under oblique incidence of circularly polarized infrared radiation the spin-galvanic effect has been unambiguously observed in (001)-grown $n$-type GaAs quantum well (QW) structures in the absence of any external magnetic field. Resonant inter-subband transitions have been obtained making use of the tunability of the free-electron laser FELIX. It is shown that a helicity dependent photocurrent along one of the $<110>$ axes is predominantly contributed by the spin-galvanic effect while that along the perpendicular in-plane axis is mainly due to the circular photogalvanic effect. This strong non-equivalence of the [110] and [1$\bar{1}$0] directions is determined by the interplay between bulk and structural inversion asymmetries. A microscopic theory of the spin-galvanic effect for direct inter-subband optical transitions has been developed being in good agreement with experimental findings.

Conference papers

• . (2011) 'Substantial temperature dependence of transverse electron g*-factor in lead chalcogenide multi-quantum wells'. AIP Conference Proceedings, 1416, pp. 178-180.

Abstract

We report significant temperature dependence of the transverse electron g*-factor in symmetric lead chalcogenide multi-quantum wells (MQWs). The g*-factor values were extracted from the electron Larmor precessions recorded by means of a circularly polarized pump probe technique under the influence of transverse external magnetic field (Voigt geometry) in the temperature range between 10 and 150K. The reported g*-factor values are in good agreement with theoretical predictions and available low temperature experimental data. Although temperature tuning of lead salt laser emission wavelengths has been the method of choice in these systems for many years, we demonstrate that temperature can also be used to modulate g*, and hence the spin lifetime in lead salt QW spintronic devices. © 2011 American Institute of Physics.

• . (2011) 'Manipulation of spin dynamics in semiconductor structures by orientation of small external magnetic field'. AIP Conference Proceedings, 1399, pp. 657-658.
• . (2011) 'Manipulation of spin dynamics in semiconductor structures by orientation of small external magnetic field'. American Institute of Physics AIP Conference Proceedings, Seoul, South Korea: ICPS2010, 30th International Conference on the Physics of Semiconductors 1399, pp. 657-658.
• . (2010) 'First Observation of a THz Photon Echo'. IEEE 35TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES (IRMMW-THZ 2010), Rome, ITALY: 35th International Conference on Infrared, Millimeter and Terahertz Waves
• . (2009) 'All Electrical Detection of the Stokes Parameters of IR/THz Radiation'. IEEE 2009 34TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER, AND TERAHERTZ WAVES, VOLS 1 AND 2, Busan, SOUTH KOREA: 34th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz 2009), pp. 298-299.
• . (2008) 'Lifetime Measurements of Group V Donor Rydberg States in Silicon at THz Frequencies'. IEEE 2008 5TH IEEE INTERNATIONAL CONFERENCE ON GROUP IV PHOTONICS, Sorrento, ITALY: 5th IEEE International Conference on Group IV Photonics, pp. 24-26.
• . (2008) 'Density and well-width dependence of the spin relaxation in n-InSb/AlInSb quantum wells'. SPRINGER NARROW GAP SEMICONDUCTORS 2007, Guildford, ENGLAND: 13th International Conference on Narrow Gap Semiconductors 119, pp. 19-21.
• . (2008) 'Temperature dependence of the electron Lande g-factor in InSb'. SPRINGER NARROW GAP SEMICONDUCTORS 2007, Guildford, ENGLAND: 13th International Conference on Narrow Gap Semiconductors 119, pp. 27-29.
• . (2007) 'Spin dynamics in narrow-gap semiconductor epitaxial layers'. SPRINGER JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM, Maui, HI: 4th International School and Conference on Spintronics and Quantum Information Technology (Spintech IV) 20 (6), pp. 461-465.
• . (2007) 'Spin lifetime in high quality InSb epitaxial layers grown on GaAs'. AMER INST PHYSICS JOURNAL OF APPLIED PHYSICS, 101 (8)
• . (2007) 'High pressure studies of mid-infrared type-II "W" diode lasers at cryogenic temperatures'. WILEY-V C H VERLAG GMBH PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS, Barcelona, SPAIN: 12th International Conference on High Pressure Semiconductor Physics (HPSP-12) 244 (1), pp. 224-228.
• . (2007) 'Carrier recombination mechanisms in mid-infrared GaInAsSb quantum well lasers'. WILEY-V C H VERLAG GMBH PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS, Barcelona, SPAIN: 12th International Conference on High Pressure Semiconductor Physics (HPSP-12) 244 (1), pp. 203-207.
• . (2006) 'Strain-symmetrized Si/SiGe multi-quantum well structures grown by molecular beam epitaxy for intersubband engineering'. ELSEVIER SCIENCE BV JOURNAL OF LUMINESCENCE, Nice, FRANCE: Symposium on Si-based Photonics held at the EMRS 2006 Conference 121 (2), pp. 403-408.
• . (2006) 'Dilute antimonide nitrides for very long wavelength infrared applications - art. no. 62060L'. SPIE-INT SOC OPTICAL ENGINEERING Infrared Technology and Applications XXXII, Pts 1and 2, Kissimmee, FL: 32nd Conference on Infrared Technology and Applications 6206, pp. L2060-L2060.
• . (2005) 'LO phonon scattering as a depopulation mechanism in Si/SiGe quantum cascades'. IEEE 2005 2nd IEEE International Conference on Group IV Photonics, Antwerp, BELGIUM: 2nd IEEE International Conference on Group IV Photonics, pp. 7-9.
• . (2005) 'Silicon quantum cascade lasers for THz sources'. IEEE 2005 IEEE LEOS Annual Meeting Conference Proceedings (LEOS), Sydney, AUSTRALIA: 18th Annual Meeting of the IEEE-Lasers-and-Electro-Optical-Society, pp. 727-728.

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