Initialization and tomography of a novel non-precessing qubit in diamond NV centers

TYPESpecial Seminar - Solid State Institute, Technion
Speaker:Guy Moshel
Affiliation:Department of Physics and the Solid State Institute, Technion
Time:12:30 - 13:30
Location:Solid State Auditorium(Entrance)
Remark:M.Sc. Student of Professor David Gershoni
  1. The Nitrogen-vacancy (NV) center in diamond is considered to be a promising candidate for quantum
    sensing and for quantum information processing. This is because at room temperature its S=1 electronics
    spin triplet is easily polarized to the m
    s =0 state by exposure to green light. The intensity of the resulting
    light emission provides a readout method for the degree of this spin polarization. The relatively long
    coherence time of the electronic spin can be utilized for quantum sensing of minute electromagnetic fields
    at the nanometer scale, as well as for quantum information processing. The natural splitting of 2.83 GHz
    between the m
    s=±1 and ms=0 state provides a tool for coherent control of the electronic spin using
    microwave radiation. Full control, requires, however, external magnetic field, which removes the
    degeneracy between the m
    s=±1 spin states. Moreover, for precise control, the magnetic field should be
    directed along the NV symmetry axis (111 and equivalent diamond crystallographic axes). We explore the
    use of polarized microwave radiation for coherent control of the m
    s=±1 spin states of the NV center, at
    vanishing external magnetic fields. This ability is important when working in amorphous samples of nanoor polycrystalline-
  2. diamonds or for other applications that require zero external magnetic fields.
    The polarized microwave radiation, provides means for selective addressing the m
    s=±1 levels using the ms=0
    as auxiliary level. We demonstrate schemes for achieving universal gates, and study the decoherence time
    of this m
    s=±1 two level system (qubit).