摘要
Quantum coherence is an important enabling feature underpinning quantum computation. However, because of couplings with its noisy surrounding environment, qubits suffer from the decoherence effects. The dynamical decoupling (DD) technique uses pulse-induced qubit flips to effectively mitigate couplings between qubits and environment. Optimal DD eliminates dephasing up to a given order with the minimum number of pulses. In this paper, we first introduce our recent work on prolonging electron spin coherence in γ-irradiated malonic acid crystals and analyze different decoherence mechanisms in this solid system. Then we focus on electron spin relaxation properties in another system, phosphorous-doped silicon (Si:P) crystals. These properties have been investigated by pulse electron paramagnetic resonance (EPR). We also investigate the performance of the dynamical decoupling technique on this system. Using 8-pulse periodic DD, the coherence time can be extended to 296 μs compared with 112 μs with one-pulse control.
Quantum coherence is an important enabling feature underpinning quantum computation. However, because of couplings with its noisy surrounding environment, qubits suffer from the decoherence effects. The dynamical decoupling （DD） technique uses pulse-induced qubit flips to effectively mitigate couplings between qubits and environment. Optimal DD eliminates dephasing up to a given order with the minimum number of pulses. In this paper, we first introduce our recent work on prolonging electron spin coherence in y-irradiated malonic acid crystals and analyze different decoherence mechanisms in this solid system. Then we focus on electron spin relaxation properties in another system, phosphorous-doped silicon （Si：P） crystals. These properties have been investigated by pulse electron paramagnetic resonance （EPR）. We also investigate the performance of the dynamical decoupling technique on this system. Using 8-pulse periodic DD, the coherence time can be extended to 296 las compared with 112 [as with one-pulse control.
基金
supported by the National Natural Science Foundation of China, the Chinese Academy of Sciences, the Ministry of Education of PRC, the National Basic Research Program of China (2007CB925200)
