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Nanometre-scale nuclear-spin device for quantum information processing

Y. Hirayama·A. Miranowicz·T. Ota·G. Yusa·K. Muraki·S. K. Ozdemir·N. Imoto
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Abstract

We have developed semiconductor point contact devices in which nuclear spins in a nanoscale region are coherently controlled by all-electrical methods. Different from the standard nuclear-magnetic resonance technique, the longitudinal magnetization of nuclear spins is directly detected by measuring resistance, resulting in ultra-sensitive detection of the microscopic quantity of nuclear spins. All possible coherent oscillations have been successfully demonstrated between two levels from four nuclear spin states of I = 3/2 nuclei. Quantum information processing is discussed based on two fictitious qubits of an I = 3/2 system and methods are described for performing arbitrary logical gates both on one and two qubits. A scheme for quantum state tomography based on Mz-detection is also proposed. As the starting point of quantum manipulations, we have experimentally prepared the effective pure states for the I = 3/2 nuclear spin system.

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Y. Hirayama, A. Miranowicz, T. Ota, G. Yusa, K. Muraki, S. K. Ozdemir, N. Imoto. 2006-05-23. Nanometre-scale nuclear-spin device for quantum information processing. https://doi.org/10.1088/0953-8984%2F18%2F21%2Fs13

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