Decoherence and Relaxation in Quantum Spin Clusters

量子自旋簇中的退相干和弛豫

基本信息

项目摘要

The major goal is to elucidate internal decoherence in few-body spin systems under unitary time-evolution. Here decoherence refers to the behavior of asubsystem.Group Schnack: We are interested in caseswhere internal decoherence is reduced similar to schemes whererelaxation and thermalization are prevented by phenomena such asmany-body localization. We plan to further investigatethe role of conservation laws, the possibility to reducedecoherence in systems of toroidal moments and the influence ofparticular external drives to refocus decohering spin systems.We also want to extend the range of investigated systems frompure spin systems to spin-phonon systems.Group Michielsen: Since quantum manipulationis no longer a future dream, but at our hands today, we propose as an application to simulatethe calculation of the ground-state energy of the Hubbard modelwith a quantum annealer. In order to take account of decoheringenvironmental spins we will study the Hubbard model embeddedinto a bath of spins by time-evolving the combined systemaccording to the time-dependent Schroedinger equation.The two Ph.D. students will interact strongly both on numericalmethods as well as on physical concepts. Goal A: Driven dynamics to improve coherence:We want to investigate the question how periodic or aperiodic stimuli/driving of system and/or bathreduces decoherence of the system. This concerns in particularthe simulation of the free-induction decay of multi-spin systemsas well as their study in the presence of Hahn echos and generalUhrig pulse sequences.Goal B: Decoherence and relaxation of toroidal moments:Like clock transitions,superpositions of states with pronounced toroidal moments may bemore robust against magnetic disturbances by other spins orfluctuating magnetic fields. Goal C: Decoherence in spin-phonon systems:We can now investigate combined systems of spins and phonons, an extension that offers veryrealistic descriptions for magnetically diluted compounds. Itwould allow to study so-called internal friction at avoidedlevel crossings induced by the phonon subsystem.Goal D: Reformulation of the Hubbard model for quantum annealing:Using the Jordan-Wigner transformation, the one-dimensionalHubbard model can be formulated as a 2N-qubit modeldefined on a two-leg ladder where the qubits on the first(second) leg of the ladder correspond to the spin-up (spin-down)fermions. We plan to study the ground state energy of the18x1 and 3x6 Hubbard model, corresponding to a36-qubit model, for various fillings by simulating the ideal analog quantumannealing process by using the Massively Parallel Quantum SpinDynamics Simulator.Goal E: Investigation of the Hubbard model:We propose to study theeffect of the environmental temperature and disorder on idealquantum annealing. We therefore simulate the quantumannealer coupled to a heat bath by solving the time-dependentSchroedinger equation of the whole system.
主要目的是阐明在幺正时间演化下少体自旋系统的内部退相干。Schnack:我们感兴趣的是内部退相干被减少的情况,类似于弛豫和热化被多体局域化等现象阻止的方案。我们计划进一步研究守恒定律的作用,降低环矩系统中相干性的可能性,以及特定外部驱动对重聚焦散肩自旋系统的影响。我们还希望将研究的系统范围从纯自旋系统扩展到自旋-声子系统。既然量子操纵不再是未来的梦想,而是在我们今天的手中,作为应用,我们提出用量子退火机模拟计算Hubbard模型的基态能量。为了考虑退相干环境自旋的影响,我们将根据含时薛定谔方程,通过对组合系统的时间演化,研究嵌入自旋池中的Hubbard模型。学生将在数值方法和物理概念上进行强烈的互动。目标A:驱动动力学,以提高一致性:我们要调查的问题,如何周期性或非周期性的刺激/驱动系统和/或浴减少系统的退相干。目标B:环向矩的退相干和弛豫:像时钟跃迁一样,具有明显环向矩的状态叠加可能对其他自旋或波动磁场的磁扰动更鲁棒。目标C:自旋-声子系统中的退相干:我们现在可以研究自旋和声子的组合系统,这是一个扩展,为磁稀释化合物提供了非常真实的描述。目标D:量子退火的哈伯德模型的重新表述:使用乔丹-维格纳变换,一维哈伯德模型可以被表述为一个定义在两条腿的梯子上的2N-量子比特模型,其中梯子的第一(第二)腿上的量子比特对应于自旋向上(自旋向下)的费米子。我们计划利用大规模并行量子自旋动力学模拟器(Massively Parallel Quantum SpinDynamics Simulator)模拟理想模拟量子退火过程,研究18 × 1和3 × 6 Hubbard模型(对应于36量子比特模型)在不同填充情况下的基态能量。目标E:Hubbard模型的研究:我们计划研究环境温度和无序度对理想量子退火的影响。因此,我们通过求解整个系统的含时薛定谔方程来模拟耦合到热浴的量子退火。

项目成果

期刊论文数量(0)
专著数量(0)
科研奖励数量(0)
会议论文数量(0)
专利数量(0)

数据更新时间:{{ journalArticles.updateTime }}

{{ item.title }}
{{ item.translation_title }}
  • DOI:
    {{ item.doi }}
  • 发表时间:
    {{ item.publish_year }}
  • 期刊:
  • 影响因子:
    {{ item.factor }}
  • 作者:
    {{ item.authors }}
  • 通讯作者:
    {{ item.author }}

数据更新时间:{{ journalArticles.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ monograph.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ sciAawards.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ conferencePapers.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ patent.updateTime }}

Professorin Dr. Kristel Michielsen其他文献

Professorin Dr. Kristel Michielsen的其他文献

{{ item.title }}
{{ item.translation_title }}
  • DOI:
    {{ item.doi }}
  • 发表时间:
    {{ item.publish_year }}
  • 期刊:
  • 影响因子:
    {{ item.factor }}
  • 作者:
    {{ item.authors }}
  • 通讯作者:
    {{ item.author }}

{{ truncateString('Professorin Dr. Kristel Michielsen', 18)}}的其他基金

Nonequilibrium dynamics in 2D clusters from the perspective of quantum typicality and eigenstate thermalization
从量子典型性和本征态热化的角度研究二维团簇中的非平衡动力学
  • 批准号:
    397067869
  • 财政年份:
  • 资助金额:
    --
  • 项目类别:
    Research Units

相似海外基金

Exact master equation for a discrete quantum system and the relaxation process
离散量子系统的精确主方程和弛豫过程
  • 批准号:
    23K03268
  • 财政年份:
    2023
  • 资助金额:
    --
  • 项目类别:
    Grant-in-Aid for Scientific Research (C)
Application of the cluster nonequilibrium relaxation scheme (generalized to quantum systems and off-critical regions) to random systems
簇非平衡弛豫方案(推广到量子系统和非临界区)在随机系统中的应用
  • 批准号:
    23K03269
  • 财政年份:
    2023
  • 资助金额:
    --
  • 项目类别:
    Grant-in-Aid for Scientific Research (C)
Modelling energy relaxation in superconducting cavities: Applications to quantum computing hardware
超导腔中的能量弛豫建模:在量子计算硬件中的应用
  • 批准号:
    564211-2021
  • 财政年份:
    2021
  • 资助金额:
    --
  • 项目类别:
    University Undergraduate Student Research Awards
Unveiling Hot Carrier Relaxation Process in Spiropyran Derivatives-Semiconductor Quantum Dots Hybrid Systems
揭示螺吡喃衍生物-半导体量子点混合系统中的热载流子弛豫过程
  • 批准号:
    21K14480
  • 财政年份:
    2021
  • 资助金额:
    --
  • 项目类别:
    Grant-in-Aid for Early-Career Scientists
He^3 Cryostat for Muon Spin Rotation/Relaxation Studies of Quantum Materials
用于量子材料 Mu 子自旋旋转/弛豫研究的 He^3 低温恒温器
  • 批准号:
    RTI-2021-00680
  • 财政年份:
    2020
  • 资助金额:
    --
  • 项目类别:
    Research Tools and Instruments
Relaxation dynamics following a quench in integrable and almost integrable quantum chains
可积和几乎可积量子链淬灭后的弛豫动力学
  • 批准号:
    421428310
  • 财政年份:
    2019
  • 资助金额:
    --
  • 项目类别:
    Research Units
Study of nonequilibrium dynamics of integrable quantum systems in association with the relaxation of isolated quantum systems and the dynamical quantum phase transition of the many-body localization
可积量子系统的非平衡动力学研究与孤立量子系统的弛豫和多体局域化的动态量子相变相关
  • 批准号:
    18K03450
  • 财政年份:
    2018
  • 资助金额:
    --
  • 项目类别:
    Grant-in-Aid for Scientific Research (C)
Relaxation dynamics of isolated many-body quantum systems: Typical behavior for a preset initial value of an observable or in the presence of additional conserved quantities.
孤立多体量子系统的弛豫动力学:可观测量的预设初始值或存在其他守恒量的典型行为。
  • 批准号:
    321992051
  • 财政年份:
    2016
  • 资助金额:
    --
  • 项目类别:
    Research Grants
He-3 Cryostat for Muon Spin Rotation/Relaxation Studies of Quantum Materials
用于量子材料 Mu 子自旋旋转/弛豫研究的 He-3 低温恒温器
  • 批准号:
    RTI-2017-00478
  • 财政年份:
    2016
  • 资助金额:
    --
  • 项目类别:
    Research Tools and Instruments
Application of InAs quantum dots with ultrafast carrier relaxation to terahertz wave detection devices
超快载流子弛豫InAs量子点在太赫兹波探测器件中的应用
  • 批准号:
    16K06266
  • 财政年份:
    2016
  • 资助金额:
    --
  • 项目类别:
    Grant-in-Aid for Scientific Research (C)
{{ showInfoDetail.title }}

作者:{{ showInfoDetail.author }}

知道了