Optical spin injection and spin lifetime in Ge heterostructures

Abstract

We demonstrate optical orientation in Ge/SiGe quantum wells and study their spin properties. The ultrafast electron transfer from the center of the Brillouin zone to its edge allows us to achieve high spin-polarization efficiencies and to resolve the spin dynamics of holes and electrons. The circular polarization degree of the direct-gap photoluminescence exceeds the theoretical bulk limit, yielding ~37% and ~85% for transitions with heavy and light holes states, respectively. The spin lifetime of holes at the top of the valence band is found to be ~0.5 ps and it is governed by transitions between heavy and light hole states. Electrons at the bottom of the conduction band, on the other hand, have a spin lifetime that exceeds 5 ns below 150 K. Theoretical analysis of the electrons spin relaxation indicates that phonon-induced intervalley scattering dictates the spin lifetime.

5 pages, 3 figures

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Cited by in corpus (36)

• An experimental demonstration of room-temperature spin transport in n-type Germanium epilayers
• Magnetic-Field-Modulated Resonant Tunneling in Ferromagnetic-Insulator-Nonmagnetic junctions
• Large enhancement in the generation efficiency of pure spin currents in Ge using Heusler-compound Co_2FeSi electrodes
• Intrinsic Spin Lifetime of Conduction Electrons in Germanium
• Donor-driven spin relaxation in multi-valley semiconductors
• Anisotropy-driven spin relaxation in germanium
• Exciton valley depolarization in monolayer transition-metal dichalcogenides
• Giant g factor tuning of long-lived electron spins in Ge
• Spin and energy relaxation in germanium studied by spin-polarized direct-gap photoluminescence
• Carrier and Spin Coherent Dynamics in Strained Germanium-Tin Semiconductor on Silicon
• Photoinduced inverse spin Hall effect in Pt/Ge(001) at room temperature
• Spin-dependent optical properties in strained silicon and germanium
• Negative orbital Hall effect in Germanium
• Spin-orbitronics at a topological insulator-semiconductor interface
• L-valley Electron Spin Dynamics in GaAs
• Suppressing spin relaxation in silicon
• Waves of spin-current in magnetized dielectrics
• Optical orientation of electron spins and valence band spectroscopy in germanium
• Magneto-optical determination of the carrier lifetime in coherent Ge(1-x)Sn(x)/Ge heterostructures
• Germanium microparticles as optically induced oscillators in optical tweezers
• Spin-dependent direct gap emission in tensile-strained Ge films on Si substrates
• Coherent Single Spin Source based on topological insulator
• Optical spin orientation and depolarization in Ge
• Experimental investigation of the optical spin selection rules in bulk Si and Ge/Si quantum dots
• Spin-dependent inter- and intra-valley electron-phonon scattering in germanium
• High temperature spin selectivity in a quantum dot qubit using reservoir spin accumulation
• Hot-electron effect in spin relaxation of electrically injected electrons in intrinsic Germanium
• Optical spin orientation of minority holes in a modulation-doped GaAs/(Ga,Al)As quantum well
• Electric Field Modulation of Spin Transport
• Resonant and Time-Resolved Spin Noise Spectroscopy
• Optical manipulation of the Rashba effect in germanium quantum wells
• Mid-Infrared Optical Spin Injection and Coherent Control
• Electron spin relaxation in X-valley of indirect bandgap AlxGa1-xAs: A new horizon for the realization of next generation spin-photonic devices
• Germanium crystals on silicon show their light
• Spin photovoltaic cell
• Optical spin pumping in silicon