Scholarlink

<p>We measure and analyze noise-induced energy-fluctuations of spin qubits defined in quantum dots made of isotopically natural silicon. Combining Ramsey, time-correlation of single-shot measurements, and CPMG experiments, we cover the qubit noise power spectrum over a frequency range of nine orders of magnitude without any gaps. We find that the low-frequency noise spectrum is similar across three different devices suggesting that it is dominated by the hyperfine coupling to nuclei. The effects of charge noise are smaller, but not negligible, and are device dependent as confirmed from the noise cross-correlations. We also observe differences to spectra reported in GaAs [Phys. Rev. Lett. 118, 177702 (2017), Phys. Rev. Lett. 101, 236803 (2008)], which we attribute to the presence of the valley degree of freedom in silicon. Finally, we observe <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\({T}_{2}^{* }\)</EquationSource> <EquationSource Format="MATHML"><math> <msubsup> <mrow> <mi>T</mi> </mrow> <mrow> <mn>2</mn> </mrow> <mrow> <mo>*</mo> </mrow> </msubsup> </math></EquationSource> </InlineEquation> to increase upon increasing the external magnetic field, which we speculate is due to the increasing field gradient of the micromagnet suppressing nuclear spin diffusion.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

The origins of noise in the Zeeman splitting of spin qubits in natural-silicon devices

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年12月9日

查看全文
  • Juan S. Rojas-Arias,
  • Yohei Kojima,
  • Kenta Takeda,
  • Peter Stano,
  • Takashi Nakajima,
  • Jun Yoneda,
  • Akito Noiri,
  • Takashi Kobayashi,
  • Daniel Loss,
  • Seigo Tarucha

摘要

We measure and analyze noise-induced energy-fluctuations of spin qubits defined in quantum dots made of isotopically natural silicon. Combining Ramsey, time-correlation of single-shot measurements, and CPMG experiments, we cover the qubit noise power spectrum over a frequency range of nine orders of magnitude without any gaps. We find that the low-frequency noise spectrum is similar across three different devices suggesting that it is dominated by the hyperfine coupling to nuclei. The effects of charge noise are smaller, but not negligible, and are device dependent as confirmed from the noise cross-correlations. We also observe differences to spectra reported in GaAs [Phys. Rev. Lett. 118, 177702 (2017), Phys. Rev. Lett. 101, 236803 (2008)], which we attribute to the presence of the valley degree of freedom in silicon. Finally, we observe \({T}_{2}^{* }\) T 2 * to increase upon increasing the external magnetic field, which we speculate is due to the increasing field gradient of the micromagnet suppressing nuclear spin diffusion.