Spontaneous spin polarization in quantum point contacts.
نویسندگان
چکیده
We use spatial spin separation by a magnetic focusing technique to probe the polarization of quantum point contacts. The point contacts are fabricated from p-type GaAs/AlGaAs heterostructures. A finite polarization is measured in the low-density regime, when the conductance of a point contact is tuned to < 2e2/h. Polarization is stronger in samples with a well-defined "0.7 structure."
منابع مشابه
Detection of spin polarization in quantum point contacts
We use spatial spin separation by a magnetic focusing technique to probe the polarization of quantum point contacts. The point contacts are fabricated from p-type GaAs/AlGaAs heterostructures. A finite polarization is measured in the low density regime, when the conductance of a point contact is tuned to <2e2/h. Polarization is stronger in samples with a well defined ‘0.7 structure’. (Some figu...
متن کاملPossible origin of the 0.5 plateau in the ballistic conductance of quantum point contacts
A non-equilibrium Green function formalism (NEGF) is used to study the conductance of a side-gated quantum point contact (QPC) in the presence of lateral spin-orbit coupling (LSOC). A small difference of bias voltage between the two side gates (SGs) leads to an inversion asymmetry in the LSOC between the opposite edges of the channel. In single electron modeling of transport, this triggers a sp...
متن کاملOrigin of the 0.5 plateau in the ballistic conductance of quantum point contacts
A non-equilibrium Green function formalism (NEGF) is used to study the conductance of a side-gated quantum point contact (QPC) in the presence of lateral spin-orbit coupling (LSOC). A small difference of bias voltage between the two side gates (SGs) leads to an inversion asymmetry in the LSOC between opposite edges of the channel. This triggers a spontaneous spin polarization, which is signific...
متن کاملSpin Polarization in GaAs/Al0.24Ga0.76As Heterostructures
The spontaneous spin polarization of a quantum point contact (QPC) formed by the lateral confinement of a highmobility two-dimensional electron gas in a GaAs/AlGaAs split gate heterostructure is investigated. Self consistent calculations of the electronic structure of the QPC are performed using the spin-polarized density functional formalism of Kohn and Sham. Spin polarization occurs at low el...
متن کاملDetecting spin-polarized currents in ballistic nanostructures.
We demonstrate a mesoscopic spin polarizer/analyzer system that allows the spin polarization of current from a quantum point contact in a large in-plane magnetic field to be measured. A transverse electron focusing geometry is used to couple current from an emitter point contact into a collector point contact. At large in-plane fields, with the point contacts biased to transmit only a single sp...
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 96 15 شماره
صفحات -
تاریخ انتشار 2006