Spin-polarized oscillations and 100% spin polarization plateau in an InAs quantum dot subjected to terahertz irradiation and a magnetic field

2015 ◽  
Vol 48 (48) ◽  
pp. 485304 ◽  
Author(s):  
R-Y Yuan ◽  
X Zhao ◽  
A-C Ji ◽  
H Yan ◽  
Y Guo
Keyword(s):  
Magnetic Field ◽  
Quantum Dot ◽  
Spin Polarization ◽  
Spin Polarized ◽  
Terahertz Irradiation ◽  
Inas Quantum Dot

Optical Pumping and Optical Detection of Spin-Polarized Electrons in a Conduction Band

1971 ◽  
Vol 49 (14) ◽  
pp. 1850-1860 ◽  
Author(s):  
R. R. Parsons
Keyword(s):  
Magnetic Field ◽  
Conduction Band ◽  
Spin Polarization ◽  
Optical Pumping ◽  
Polarized Light ◽  
Degree Of Polarization ◽  
Polarized Electrons ◽  
Excitation Light ◽  
Circularly Polarized Light ◽  
Spin Polarized

Spin-polarized electrons are created in the conduction band of p-type GaSb by excitation with σ+ or σ− circularly polarized light. The degree of polarization of the photoluminescence is used to measure the optically pumped spin polarization. The measurements as a function of transverse magnetic field yield the spin-relaxation time and the lifetime of the photocreated electrons. The degree of polarization oscillates as a function of the photon energy of the excitation light. This effect is associated with mechanisms of rapid energy loss involving optical and acoustical phonons. The optical pumping is studied as a function of temperature in the range 3.5 °K ≤ T ≤ 11 °K. A maximum spin polarization [Formula: see text] is obtained at [Formula: see text]. The efficiency of the optical pumping is significantly increased with the application of a weak longitudinal magnetic field.

Spin Polarized Transport through Structures Consist of the Ferromagnetic Semiconductor in Presence of a Inhomogeneous Magnetic Field

2011 ◽  
Vol 194-196 ◽  
pp. 679-682
Author(s):  
Zahra Bamshad
Keyword(s):  
Magnetic Field ◽  
Spin Polarization ◽  
Fermi Energy ◽  
Magnetic Tunnel Junction ◽  
Inhomogeneous Magnetic Field ◽  
Spin Polarized ◽  
Polarized Transport ◽  
Dimensional Electron Gas ◽  
Spin Electronic ◽  
Spin Polarized Transport

The spin-polarized transport is investigated in a magnetic tunnel junction which consists of two ferromagnetic electrodes separated by a magnetic barrier and a nonmagnetic metallic spacer placed in distance above the two dimensional electron gas (2DEG) in presence of an inhomogeneous external modulated magnetic field and a perpendicular wave vector dependent effective potential. Based on the transfer matrix method and the nearly-free-electron approximation the dependence of the conductance and spin polarization on the Fermi energy of the electrons are studied theoretically the. strong oscillations with large amplitude investigated in spin polarization in terms of the Fermi energy due to the inhomogeneous magnetic field. The conductance in terms of the Fermi energy shows no oscillation in low energy but has a strong pick in middle region. this results may be useful for the development of spin electronic devices based on coherent transport, or may be used as a tunable spin-filter.

Nuclear spin polarization by out-of-plane spin injection from ferromagnet into an InAs heterostructure

2012 ◽  
Vol 1396 ◽  
Author(s):  
Tomotsugu Ishikura ◽  
Takahiro Hiraki ◽  
Takashi Matsuda ◽  
Joungeob Lee ◽  
Kanji Yoh
Keyword(s):  
Magnetic Field ◽  
Spin Polarization ◽  
Nuclear Spin ◽  
Spin Injection ◽  
Hall Voltage ◽  
Nuclear Spin Polarization ◽  
Polarized Electrons ◽  
Spin Polarized ◽  
Magnetic Metal ◽  
Out Of Plane

AbstractWe have investigated an InAs channel Hall-bar structure with ferromagnetic spin injector in one of the current terminals. After magnetizing the Fe electrode, spin polarized electrons are injected through the edge of the isolation mesa structure and the anomalous Hall voltage is observed, when electrons are injected from the ferromagnetic terminal. However, when electrons are injected from the non-magnetic metal (Ti/Au) of opposite terminal, the Hall voltage disappeared to the variation error level due to the fabrication imperfections. This result suggests the possibility that out-of-plane spin injection from the channel edge lead to perpendicular nuclear magnetic field. It is presumably caused by nuclear spin polarization in InAs channel near the spin source edge through Overhauser effect. The estimated internal magnetic field was 2000 Gauss.

Sign in / Sign up

Export Citation Format

Share Document