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...
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عنوان ژورنال:
- Physical review letters
دوره 96 15 شماره
صفحات -
تاریخ انتشار 2006