Laser-polarimetric measurements of magnetic ac-susceptibility in LiYF4: Ho3+ crystals

Experimental measurement of the isolated magnetic susceptibility

“…tal data [19][20][21][22][23], it appears that a simple reduction to a well defined isolated susceptibility has not been previously observed. Our observation of it in dilute spin ice has been enabled by the unique local environment of the Ho 3+ , which allows a very simple effective Hamiltonian to be enacted.…”

“…More generally, a strongly structured nuclearelectronic response is indeed a long established behavior [18] of dilute Ho 3+ ions in crystals, which have been impressively analysed with master equation-based approaches in several works [19][20][21][22][23]. In general, various transitions are possible depending upon coupling with the local environment of the effective spins, which gener- ates a combination of intrinsic and interaction-induced direct and avoided level crossings, respectively.…”

Evolution of spin relaxation processes in LiY1−xHoxF4Johnson1, Малкин2, Lord3 et al. 2012Phys. Rev. BSelf Cite8070View full textAdd to dashboardCite

“…All concentration-independent parameters which we use in simulations of the AC-susceptibilities have been determined in previous studies of optical and EPR spectra, 19 F nuclear spin relaxation and AC-susceptibilities in low-x LiY 1-x Ho x F 4 samples (x ≤ 0.0027). 6,7,8,24 In particular, crystal field parameters in the Hamiltonian H CF and electron-phonon coupling constants used in calculations of the relaxation rates are given in Table I …”

“…14 This was further developed into a microscopic theory of relaxation rates through numerical simulations which take into account the effects of crystal field, electronphonon, and hyperfine interactions, as well as cross-relaxation processes. 6,7 At low frequencies, peaks (dips) in the field dependences of the in-phase and out-of-phase susceptibilities (hereafter referred to as ' χ and '' χ , respectively) indicate enhanced relaxation processes that occur at the field-induced ALCs. Additional peaks (dips) in ' χ ( '' χ ) at n > 7, along with smaller peaks in ' χ and '' χ at half-integer n values (-13 ≤ 2n ≤ 13), have also been observed and explained.…”

“…3,4 The lattice constants are almost unchanged with a variation of x, and large, high quality single crystals are available, making this system ideal for both experimental and theoretical studies. The very dilute limit (x < 0.005) has been recently studied as well, and is a paradigm system for studying quantum tunneling of the magnetization; 5 for example, the single-ion spin dynamics have been accurately modeled to reproduce AC-susceptibility 6,7 and 19 F nuclear spin-lattice relaxation data. 8 However, the nature of the low-temperature ground state for intermediate concentrations remains controversial.…”