RAC1 Journal Club/Seminar Series

Canadian Graduate Quantum Conference (CGQC) Practice Talk Session

Bowen Yang, Masters Student

Rahul Deshpande, PhD Student

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Bowen Yang

One million percent tunnel magnetoresistance in magnetic van der Waals heterostructure

We report the observation of a very large negative magnetoresistance effect in a van der Waals tunnel junction incorporating a thin magnetic semiconductor, CrI3, as the active layer. Current increases by nearly one million percent upon application of a 2 Tesla field. The effect arises from a phase transition between antiferromagnetic to ferromagnetic alignment of spins between CrI3 layers. Our results elucidate the nature of the magnetic state in ultrathin CrI3 and present new opportunities for spintronics based on two-dimensional materials.

Rahul Deshpande

​Optical Hyperpolarization Mechanism for 31P Defects in Isotopically Purified Silicon

31P nuclear spins in phosphorus doped silicon are a promising candidate for quantum sensors and as a platform for quantum computing due to their long coherence times and the ability to hyperpolarize the spins using various optical methods. In this talk, I will describe our investigation of the mechanism that leads to phosphorus hyperpolarization in the presence of above bandgap light and how our approach also allows us to measure the rates of bound exciton formation and Auger recombination at the phosphorus defect sites in silicon.

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