NMR Measurements on New Quantum Phases in 2D ³He

Monolayer ³He is an ideal experimental system for studying strongly correlated two dimensional fermions. We measured magnetic properties of the second layer of ³He adsorbed on ⁴He‐preplated graphite by NMR in a wide temperature (70 μK. < T < 300 mK) and density (4.9 < p <9.8 nm⁻²) ranges. The measured magnetization isotherms can be classified into four distinct regions depending on density. The present NMR results support the scenario given by the recent heat capacity measurements that the region just below the density for the 4/7 commensurate phase is a hole‐doped Mott localized phase.