Ultra-deep optical cooling of coupled nuclear spin-spin and quadrupole reservoirs in a GaAs/(Al,Ga)As quantum well

AbstractThe physics of interacting nuclear spins in solids is well interpreted within the nuclear spin temperature concept. A common approach to cooling the nuclear spin system is adiabatic demagnetization of the initial, optically created, nuclear spin polarization. Here, the selective cooling of 75As spins by optical pumping followed by adiabatic demagnetization in the rotating frame is realized in a nominally undoped GaAs/(Al,Ga)As quantum well. The lowest nuclear spin temperature achieved is 0.54 μK. The rotation of 6 kG strong Overhauser field at the 75As Larmor frequency of 5.5 MHz is evidenced by the dynamic Hanle effect. Despite the presence of the quadrupole induced nuclear spin splitting, it is shown that the rotating 75As magnetization is uniquely determined by the spin temperature of coupled spin-spin and quadrupole reservoirs. The dependence of heat capacity of these reservoirs on the external magnetic field direction with respect to crystal and structure axes is investigated.

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Strong Coupling of Electron and Nuclear Spins: Outlook and Prospects

10.1093/oso/9780198807308.003.0011 ◽

2018 ◽

Author(s):

M. M. Glazov

Keyword(s):

Energy Spectrum ◽

Charge Carrier ◽

Strong Coupling ◽

Nuclear Spin ◽

Spin Dynamics ◽

Spin Polaron ◽

Nuclear Spins ◽

Deep Impurity ◽

Impurity Centers ◽

Ordered State

In this chapter, some prospects in the field of electron and nuclear spin dynamics are outlined. Particular emphasis is put ona situation where the hyperfine interaction is so strong that it leads to a qualitative rearrangement of the energy spectrum resulting in the coherent excitation transfer between the electron and nucleus. The strong coupling between the spin of the charge carrier and of the nucleus is realized, for example in the case of deep impurity centers in semiconductors or in isotopically purified systems. We also discuss the effect of the nuclear spin polaron, that is ordered state, formation at low enough temperatures of nuclear spins, where the orientation of the carrier spin results in alignment of the spins of nucleus interacting with the electron or hole.

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Optical pumping of IV-VI semiconductor multiple quantum well materials using a GaSb-based laser with emission at λ=2.5μm

Journal of Applied Physics ◽

10.1063/1.1851601 ◽

2005 ◽

Vol 97 (5) ◽

pp. 053103 ◽

Cited By ~ 7

Author(s):

P. J. McCann ◽

P. Kamat ◽

Y. Li ◽

A. Sow ◽

H. Z. Wu ◽

...

Keyword(s):

Quantum Well ◽

Optical Pumping ◽

Multiple Quantum Well ◽

Multiple Quantum

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High-efficiency optical pumping of nuclear polarization in a GaAs quantum well

Physical Review B ◽

10.1103/physrevb.96.201303 ◽

2017 ◽

Vol 96 (20) ◽

Cited By ~ 1

Author(s):

R. W. Mocek ◽

V. L. Korenev ◽

M. Bayer ◽

M. Kotur ◽

R. I. Dzhioev ◽

...

Keyword(s):

Quantum Well ◽

Nuclear Polarization ◽

Optical Pumping ◽

High Efficiency

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Effective collinear optical pumping for nuclear spin polarization

Journal of the Optical Society of America B ◽

10.1364/josab.31.002278 ◽

2014 ◽

Vol 31 (10) ◽

pp. 2278 ◽

Cited By ~ 1

Author(s):

Sung Jong Park ◽

Taeksu Shin ◽

Ju Hahn Lee ◽

Gi Dong Kim ◽

Yong Kyun Kim

Keyword(s):

Spin Polarization ◽

Nuclear Spin ◽

Optical Pumping ◽

Nuclear Spin Polarization

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Erratum: Zero-field spin splitting and spin lifetime inn-InSb∕In1−xAlxSbasymmetric quantum well heterostructures [Phys. Rev. B77, 165335 (2008)]

Physical Review B ◽

10.1103/physrevb.78.079901 ◽

2008 ◽

Vol 78 (7) ◽

Author(s):

A. M. Gilbertson ◽

M. Fearn ◽

J. H. Jefferson ◽

B. N. Murdin ◽

P. D. Buckle ◽

...

Keyword(s):

Quantum Well ◽

Spin Splitting ◽

Zero Field ◽

Spin Lifetime

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High-Power Low-Threshold Optically Pumped Type-ll Quantum-Well Lasers

MRS Proceedings ◽

10.1557/proc-484-107 ◽

1997 ◽

Vol 484 ◽

Author(s):

Chih-Hsiang Lin ◽

S. J. Murry ◽

Rui Q. Yang ◽

S. S. Pei ◽

H. Q. Le ◽

...

Keyword(s):

Quantum Well ◽

Output Power ◽

Optical Pumping ◽

Internal Quantum Efficiency ◽

Characteristic Temperature ◽

Stimulated Emission ◽

Free Carrier Absorption ◽

Type Ii ◽

Optically Pumped ◽

Internal Loss

AbstractStimulated emission in InAs/InGaSb/InAs/AlSb type-II quantum-well (QW) lasers was observed up to room temperature at 4.5 μm, optically pumped by a pulsed 2-μm Tm:YAG laser. The absorbed threshold peak pump intensity was only 1.1 kW/cm2 at 300 K, with a characteristic temperature T0 of 61.6 K for temperatures up to 300 K. We will also study the effects of internal loss on the efficiency and output power for type-II QW lasers via optical pumping. Using a 0.98-μm InGaAs linear diode array, the devices exhibited an internal quantum efficiency of 67% at temperatures up to 190 K, and was capable of < 1. 1-W peak output power per facet in 6-μs pulses at 85 K. The internal loss of the devices exhibited an increase from 18 cm−1 near 70 K to ∼ 60–100 cm−1 near 180 K, which was possibly due to inter-valence band free carrier absorption.

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Adiabatic demagnetization at absolute negative temperature: Generation of quantum correlations

International Journal of Quantum Information ◽

10.1142/s0219749919500230 ◽

2019 ◽

Vol 17 (03) ◽

pp. 1950023

Author(s):

Gregory B. Furman ◽

Shaul D. Goren ◽

Victor M. Meerovich ◽

Vladimir L. Sokolovsky

Keyword(s):

Magnetic Field ◽

Negative Temperature ◽

Quantum Correlations ◽

Zero Magnetic Field ◽

Positive Temperature ◽

Nuclear Spins ◽

Adiabatic Demagnetization ◽

Negative Temperatures ◽

Classical Correlations ◽

Quantum And Classical Correlations

In this paper, we study behavior of the correlations, both quantum and classical, under adiabatic demagnetization process in systems of nuclear spins with dipole–dipole interactions in an external magnetic field and in the temperature range including positive and negative temperatures. For a two-spin system, analytical expressions for the quantum and classical correlations are obtained. It is revealed that the field dependences of the quantum and classical correlations at positive and negative temperatures are substantially different. This difference most clearly appears in the case of zero magnetic field: at negative temperature, the measures of quantum correlations tend to the maximum values with a temperature increase. At positive temperature, these quantities tend to zero at a decrease of magnetic field. It is also found that, for the nearest-neighboring spins in the same field, the values of concurrence and discord are larger at negative temperatures than at positive ones.

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