Material Science with Muon and Unstable Nuclei Probes
TRIUMF in the south campus of UBC provides the No.1 opportunity in North America to investigate materials properties with muons and unstable nuclei.
Kenji M. Kojima has been an external user of TRIUMF muon facility since 1991, and started an independent research program as a local research scientist in the summer of 2018.
A muon (positive µ+ or negative µ-) is the second heaviest lepton next to positron e+ or electron e-. Nice feature of a muon (particularly the positive µ+) is that it is spin polarized, and utilized as a probe of magnetic field inside the matter.
TRIUMF has been extensively used for materials science, with its positive muon beam as the probe of magnetism and superconductivity, which can never been investigated by other experimental techniques due to their limited sensitivities.
Positive muon is also userd as a light isotope of proton. In semiconductors, their electronic properties are often altered by a small amout of hydrogen impurities; positive muon has been used to investigate such role of hydrogens in semiconductors in their dilute limit.

Unstable nuclei is available at ISAC facility of TRIUMF.
Particularly, 8Li nucleus is useful in materials science; it has the same features which a muon has (spin polarization and polarization dependent emission of electron), but an extended lifetime. The measurement time window is determined by the lifetime of the probe partiles (1.2 seconds for 8Li and 2.2 µsec for muon), which determines the kind of phenomena each probe is sensitive to.
Also, the low energy feature of 8Li beam (in the order of keV whereas muons are in MeV) makes the investigation of nano-meter thick thin films possible, which utilizes future research of working elecronic devices.