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Influence of time-periodic potentials on electronic transport in double-well structure

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Chinese Physics B 2010年第5期19卷 488-493页

作者：李春雷徐燕 College of Elementary Educational Capital Normal University

Within the framework of the Floquet theorem, we have investigated single-electron photon-assisted tunneling in a double-well system using the transfer matrix technique. The transmission probability displays satellite peaks on both sides of the main resonance peaks and these satellite peaks originate from emission or absorption photons. The single-electron resonance tunneling can be controlled through changing the applied harmonically potential positions, such as driven potential in wells, in barriers, or in whole double-well systems. This advantage should be useful in the optimization of the parameters of a transmission device.

关键词： photon-assisted tunneling transmission probability quantum well

Modulated Quasi-plane Tunneling Current

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 44-46页

作者： Peng Feng Wenmin Dai (China Center of Advanced Science & Technology (World Laboratory ) P.O. Box 8730, Beijing 100080, China)(Applied Science School, University of Science and Technology Beijing, Beijing 100083, China) China Center of Advanced Science and Technology (World Laboratory) P.O. Box 8730 Beijing 100080 China Applied Science School University of Science and Technology Beijing Beijing 100083 China

A new tutmeling junction can be formed by an insulator layer inserting into a quantum well, and in the quantum well, a quasi-plane tunneling current can be formed by applying a tunneling voltage. If a P-N junction is grown on the quantum well, the tunneling current can be modulated by a P-N junction-bias voltage. The modulated quasi-plane tunneling current is not only related to the bias voltage, but also to the depth of the quantum well. It is analyzed that the P-N junction-bias voltage how to affect the tunneling current and a method of measuring the depth of the quantum well is presented.

关键词： quantum well tunneling current semiconductor device

Optical property and lasing of GaAs-based nanowires

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Science China Materials 2020年第8期63卷 1364-1381页

作者： Haolin Li Yuting Chen Zhipeng Wei Rui Chen State Key Laboratory of High Power Semiconductor Laser School of ScienceChangchun University of Science and TechnologyChangchun 130022China Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China

GaAs-based nanowire(NW)lasers working in the infrared region is critical in integrated *** the past few decades,the field of NW lasers has developed *** with materials working in the ultraviolet and visible ranges,GaAs-based infrared NW lasers,however,are more difficult to achieve because of their specific *** this review,we focus on the recent developments of GaAs-based NWs,more especially,the optical property and lasing of GaAs-based *** growth mechanism of GaAs NWs is introduced in detail,including the crystal phase control and the growth of complex ***,the influence and improvement of the optical properties of GaAsbased NWs are introduced and ***,the design and latest progress of GaAs-based NW lasers are put forward.

关键词： GaAs-based nanowires quantum well infrared op tical property lasing

Interband cascade lasers with short electron injector

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Chinese Optics Letters 2022年第2期20卷 142-147页

作者： Chao Ning Tian Yu Shuman Liu Jinchuan Zhang Lijun Wang Junqi Liu Ning Zhuo Shenqiang Zhai Yuan Li Fengqi Liu Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices Key Laboratory of Semiconductor Materials ScienceInstitute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Opto-Electronic Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Academy of quantum Information Sciences Beijing 100193China

We demonstrate Ga Sb-based interband cascade lasers(ICLs) emitting around 3.65 μm, which exhibit a room-temperature continuous-wave(CW) output power above 100 m W. Cavity-length analysis showed that the laser structure has a low internal loss of 3 cm^(-1) while maintaining a total internal quantum efficiency greater than one. After 6400 h CW operation at 25°C,the threshold current of the laser increased by 3%, and the output power decreased by 7%, indicating good reliability of the device.

关键词： interband cascade lasers quantum well mid-infrared semiconductor lasers

An efficient approach to characterizing and calculating carrier loss due to heating and barrier height variation in vertical-cavity surface-emitting lasers

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Chinese Physics B 2010年第1期19卷 361-365页

作者：吴坚 H.D.Summers School of Physics and Nuclear Energy Engineering Beijing University of Aeronautics and Astronautics School of Physics and Astronomy Cardiff University

It is important to determine quantitatively the internal carrier loss arising from heating and barrier height variation in a vertical-cavity surface-emitting quantum well laser （VCSEL）. However, it is generally difficult to realize this goal using purely theoretical formulas due to difficulty h, deriving the parameters relat^i~g to the quantum well structure. In this paper, we describe an efl：icient approach to characterizing and calculating the carrier loss due to the heating and the barrier height change in the VCSEL. In the method, the thermal carrier loss mechanism is combined with gain measurement and calculation. The carrier loss is re-characterized in a calculable form by constructing the threshold current and gain detuning-related loss current using the measured gain data and then substituting them for the quantum well-related parameters in the formula. The result can be expressed as a product of an exponential weight factor linked to the barrier height change and the difference between the threshold current and gain detuning-related loss current. The gain variation at cavity frequency due to thermal carrier loss and gain detuning processes is measured by using an AllnGaAs-AIGaAs VCSEL structure. This work provides a useful approach to analysing threshold and loss properties of the VCSEL, particularly, gain offset design for high temperature operation of VCSELs.

关键词： semiconductor laser vertical cavity surface emitting laser quantum well thermal carrier loss

Magnetic polarization of a Mn-doped semiconductor nanostructure controlled by an external bias

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Journal of Semiconductors 2015年第7期36卷 22-28页

作者： P.Paradeo Unstituto de Fisica Universidad Nacional Autonoma de Mexico

The interplay between the electric and magnetic properties in a double quantum well heterostructure doped by magnetic ions is theoretically investigated. In this material, the magnetism is mediated by the hole gas. The total magnetic polarization of the system is controllable by an external applied bias. The device has two equilibrium states （symmetric and antisymmetric configurations）. In the stable configuration （anti-ferromagnetic type）, the particle spin distribution is reversed in the adjacent wells. The stability of the system is investigated by simulating the interaction of the hole gas with the light. By using an ab initio method, we estimate the switching time of the device.

关键词： magnetic polarization quantum well stability

Dynamics of dense spin ensemble excited in a barrier layer and detected in a well

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Science China(Physics,Mechanics & Astronomy) 2011年第6期54卷 1108-1111页

作者： SHEN Chao WANG LiGuo ZHU Hui ZHENG HouZhi State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesP.O.Box 912Beijing 100083China

Photoluminescence (PL) polarization of a spin ensemble was examined over a wide excitation wavelength range from 520 nm to 700 nm and a temperature range from 3.5 K to 300 K after it transfers from a (AlGa)As barrier layer and eventually quenches irradiatively in a GaAs quantum well (QW).A highest PL circular polarization of 30% can be kept at temperatures up to 120 K,while its room temperature value reaches about 17%.It is found that the main features of the optical spin orientation in bulk Al 0.27 Ga 0.73 As materials can be reproduced in terms of the wavelength dependence of PL polarization degree,as the spin polarized ensemble transfers and relaxes into GaAs *** transient of PL polarization degree also indicates that a dense spin ensemble collected from the barrier region is in favor of conserving its polarization in GaAs QW as evidenced by a rising temporal response.

关键词： spin polarized transport optical orientation dense spin relaxation quantum well

Polaronic effect on a bound polaron

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2002年第5期3卷 75-79页

作者：阮永红吴福理陈庆虎 Department of Physics Zhejiang University Hangzhou China

Feynman variational path integral theory was used to obtain the ground state energy of a polaron in a quantum well in the presence of a Coulomb potential for arbitrary values of the electron phonon coupling constant α . Numerical and analytical results showed that the energy shift was more sensitive to α than to the Coulomb binding parameter ( β ) and increased with the decrease of effective quantum well width l Z . It was interesting that due to the electronic confinement in the quasi 2D (quantum well) structures, the lower bound of the strong coupling regime was shifted to smaller values of α . Comparison of the polaron in the quantum well with that in the quantum wire or dot showed that the polaronic effect strengthened with decrease of the confinement dimension.

关键词： Bound polaron quantum well quantum wire quantum dot Ground state energy

Suppression of electron leakage in 808 nm laser diodes with asymmetric waveguide layer

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Journal of Semiconductors 2016年第1期37卷 69-72页

作者：李翔赵德刚江德生陈平刘宗顺朱建军侍铭赵丹梅刘炜 State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of SciencesBeijing 100083 China

Electron leakage in GaAs-based separately confined heterostructure 808 nm laser diodes （SCH LDs） has a serious influence on device performance. Here, in order to reduce the energy of electrons injected into the quantum well （QW）, an A1GaAs interlayer with a smaller A1 component is added between the active region and the n-side waveguide. Numerical device simulation reveals that when the Al-composition of the A1GaAs interlayer and its thickness are properly elected, the electron leakage is remarkably depressed and the characteristics of LDs are improved, owing to the reduction of injected electron energy and the improvement of QW capture efficiency.

关键词： quantum well laser diodes electron leakage electron energy