Mani Arjun, Pal Subhajit, Benjamin Colin
School of Physical Sciences, National Institute of Science Education & Research, HBNI, Jatni, 752050, India.
Sci Rep. 2019 Apr 12;9(1):6018. doi: 10.1038/s41598-019-42279-7.
We design a quantum spin heat engine using spin polarized ballistic modes generated in a strained graphene monolayer doped with a magnetic impurity. We observe remarkably large efficiency and large thermoelectric figure of merit both for the charge as well as spin variants of the quantum heat engine. This suggests the use of this device as a highly efficient quantum heat engine for charge as well as spin based transport. Further, a comparison is drawn between the device characteristics of a graphene spin heat engine against a quantum spin Hall heat engine. The reason being edge modes because of their origin should give much better performance. In this respect we observe our graphene based spin heat engine can almost match the performance characteristics of a quantum spin Hall heat engine. Finally, we show that a pure spin current can be transported in our device in absence of any charge current.
我们设计了一种量子自旋热机，它利用在掺杂有磁性杂质的应变石墨烯单层中产生的自旋极化弹道模式。我们观察到，对于量子热机的电荷和自旋变体，其效率和热电品质因数都非常大。这表明该装置可作为基于电荷和自旋输运的高效量子热机。此外，还对石墨烯自旋热机与量子自旋霍尔热机的器件特性进行了比较。原因在于边缘模式，由于其起源，应能提供更好的性能。在这方面，我们观察到基于石墨烯的自旋热机几乎可以与量子自旋霍尔热机的性能特征相匹配。最后，我们表明在没有任何电荷电流的情况下，纯自旋电流可以在我们的器件中传输。
