Nuclear spin switch in semiconductor quantum dots.
نویسندگان
چکیده
We show that by illuminating an InGaAs/GaAs self-assembled quantum dot with circularly polarized light, the nuclei of atoms constituting the dot can be driven into a bistable regime, in which either a thresholdlike enhancement or reduction of the local nuclear field by up to 3 T can be generated by varying the pumping intensity. The excitation power threshold for such a nuclear spin "switch" is found to depend on both the external magnetic and electric fields. The switch is shown to arise from the strong feedback of the nuclear spin polarization on the dynamics of the spin transfer from electrons to the nuclei of the dot.
منابع مشابه
Nuclear Spin Phenomena in Optically Active Semiconductor Quantum Dots
The motivating background for this thesis lies in the recent development in the coherent optical control of electron spin states in semiconductor quantum dots. One possible and attractive application for these achievements is a physical implementation of a quantum computer based on spin qubits (quantum bit) in quantum dots. However, one of the obstacles in building such quantum computer is deco...
متن کاملNuclear spin effects in semiconductor quantum dots.
The interaction of an electronic spin with its nuclear environment, an issue known as the central spin problem, has been the subject of considerable attention due to its relevance for spin-based quantum computation using semiconductor quantum dots. Independent control of the nuclear spin bath using nuclear magnetic resonance techniques and dynamic nuclear polarization using the central spin its...
متن کاملElectron spin relaxation by nuclei in semiconductor quantum dots
We have studied theoretically the electron spin relaxation in semiconductor quantum dots via interaction with nuclear spins. The relaxation is shown to be determined by three processes: (i) – the precession of the electron spin in the hyperfine field of the frozen fluctuation of the nuclear spins; (ii) – the precession of the nuclear spins in the hyperfine field of the electron; and (iii) – the...
متن کاملElectron and nuclear spins in semiconductor quantum dots
The electron and nuclear spin degrees of freedom in two-dimensional semiconductor quantum dots are studied as important resources for such fields as spintronics and quantum information. The coupling of electron spins to their orbital motion, via the spinorbit interaction, and to nuclear spins, via the hyperfine interaction, are important for understanding spin-dynamics in quantum dot systems. T...
متن کاملSpin textures in strongly coupled electron spin and magnetic or nuclear spin systems in quantum dots.
Controlling electron spins strongly coupled to magnetic and nuclear spins in solid state systems is an important challenge in the field of spintronics and quantum computation. We show here that electron droplets with no net spin in semiconductor quantum dots strongly coupled with magnetic ion or nuclear spin systems break down at low temperature and form a nontrivial antiferromagnetic spatially...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical review letters
دوره 98 2 شماره
صفحات -
تاریخ انتشار 2007