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تسجيل مستخدم جديدTheory of NMR in semiconductor quantum point contact devices
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We describe how a local non-equilibrium nuclear polarisation can be generated and detected by electrical means in a semiconductor quantum point contact device. We show that measurements of the nuclear spin relaxation rate will provide clear signatures of the interaction mechanism underlying the 0.7 conductance anomaly. Our analysis illustrates how nuclear magnetic resonance methods, which are used extensively to study strongly-correlated electron phases in bulk materials, can be made to play a similarly important role in nanoscale devices.
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We propose a probe based on nuclear relaxation and Knight shift measurements for the Kondo scenario for the 0.7 feature in semiconductor quantum point contact (QPC) devices. We show that the presence of a bound electron in the QPC would lead to a muc
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