Magnetic excitations in uniaxial-strained α-RuCl3

The concept of the quantum spin liquid (QSL) was originally proposed by Anderson in 1973, describing a correlated system that does not order even at zero temperature. Among various proposals for QSL, α-RuCl3 has attracted particular attention. It is worth noting that the spin waves exhibiting six-fold symmetry and the spin-excitation continuum showing isotropic feature were actually measured on twinned crystals. Previously, structure and magnetic twinning domains were found in most α-RuCl3 crystals at low temperatures. At Ts≈80-160K, α-RuCl3 undergoes a first-order structural transition and enters a C2/m structure. The structural transition with a significant change in lattice parameter provides a possibility of detwinning the sample using uniaxial strain. At TN=6-14K, α-RuCl3 enters a zigzag order state. There are three possible configurations of zigzag orders, corresponding to the C2 symmetric magnetic Brillouin zones and antiferromagnetic wave vectors. The coexistence of the three magnetic twinning domains results in the C6 symmetric spin waves and the isotropic excitation continuum. To better understand the magnetic ground state and the magnetic interactions, measuring the spin excitations in detwinned samples is necessary. Thus, we propose to study the spin excitations of uniaxial-strained α-RuCl3 with uniaxial strain upto 0.6% using a low-background uniaxial strain device.