Materials Characterization for Quantum Computation

量子计算的材料表征

• 批准号: 531520-2018
• 负责人: Kycia, Jan
• 金额: $ 1.82万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=656221
• 关键词: Materials; Characterization; Quantum; Computation

This project involves testing state of the art superconducting devices used for quantum computing and quantum**information processing. The building block of the superconducting quantum computer is the Josephson**junction. This is typically a sub-micron scaled tunnel junction lithographically patterned from a trilayer of**Nb/AlOx/Nb. For quantum computing as well as high performance SQUID sensors, this superconducting**device must have a very stable quantum tunneling resistance. Materials aspects have been found to be**responsible for the ultimate noise limit for such devices. For example, defects within or in the vicinity of the**oxide barrier can fluctuate causing a low frequency noise (1/f noise) in the tunneling resistance. Similarly**magnetic particles on the surface of the device can fluctuate, causing 1/f noise in the background magnetic flux**seen by the device. For the application of quantum computing, this noise causes decoherence, which is a loss of**the quantum information. This limits the effectiveness of the qubit. In the case of SQUID magnetometers, this**produces a residual magnetic noise that limits the sensitivity of the sensor.**The proposed project will work with D-wave, a company working on superconducting quantum computation,**to set up a reliable, efficient way to characterize the quality of the Josephson junction based devices in order to**make higher performance quantum computers.**

该项目涉及测试用于量子计算和量子信息处理的最先进的超导设备。超导量子计算机的构建块是约瑟夫森结。这通常是由 **Nb/AlOx/Nb三层光刻图案化的亚微米级隧道结。对于量子计算以及高性能SQUID传感器，这种超导 ** 器件必须具有非常稳定的量子隧穿电阻。材料方面已被发现是负责这种设备的最终噪声限值。例如，** 氧化物势垒内或附近的缺陷可能波动，导致隧穿电阻中的低频噪声（1/f噪声）。类似地，** 设备表面的磁性颗粒可能会波动，导致设备看到的背景磁通量 ** 中的1/f噪声。对于量子计算的应用，这种噪声会导致退相干，这是量子信息的损失。这限制了量子比特的有效性。对于SQUID磁强计，这会产生残余磁噪声，限制传感器的灵敏度。该项目将与D-wave公司合作，该公司致力于超导量子计算，** 建立一种可靠，有效的方法来表征基于约瑟夫森结的设备的质量，以便 ** 制造更高性能的量子计算机。