APS March Meeting 2017
Volume 62, Number 4
Monday–Friday, March 13–17, 2017;
New Orleans, Louisiana
Session B35: Experimental Techniques and Results: Static High Pressure Physics
11:15 AM–2:15 PM,
Monday, March 13, 2017
Room: 298
Sponsoring
Units:
DCMP DMP
Abstract ID: BAPS.2017.MAR.B35.13
Abstract: B35.00013 : Extreme conditions magnetostriction study of the Shastry-Sutherland sample SCBO*
1:39 PM–1:51 PM
Preview Abstract
Abstract
Authors:
Audrey Grockowiak
(National High Magnetic Field Laboratory)
Björn Wehinger
(University of Geneva)
William Coniglio
(National High Magnetic Field Laboratory)
Chistian Ruegg
(Paul Scherrer Institute)
Stanley Tozer
(National High Magnetic Field Laboratory)
Collaborations:
National High Magnetic Field Laboratory, Paul Scherrer Institute
The Shasty--Sutherland model, which consists of a set of spin 1/2 dimers on
a 2D square lattice, is simple and soluble but captures a central theme of
condensed matter physics by sitting precariously on the quantum edge between
isolated, gapped excitations and collective, ordered ground states. This
model is realized in SrCu2(BO3)2. Recent x-ray diffraction data revealed a
direct correlation of the lattice with magnetic susceptibility measurements
at low temperatures [1]. The variation of the lattice parameters with
temperature is thus directly linked to the spin response of the system.
Indeed, scattering intensities from the spin waves, measured by inelastic
neutron scattering experiments, decay accordingly [2]. The magnetic
correlations can thus be monitored by the lattice parameters and are thus
sensitive to magnetostriction. Ambient pressure magnetostriction up to 100.7
T [5, 6] show clear signatures related to the magnetization plateaus at 30,
40 and 80T. Together with total energy calculations these studies revealed a
strong magneto elastic coupling driven by the super exchange angle CuOCu.
Applying hydrostatic external pressure results in continuous and
discontinuous quantum phase transitions [1,3]. Zero field high pressure
neutron spectroscopy measurements have revealed so far three phases : spin
dimer from 0 to 2GPa, antiferromagnetic from 4 to 6 GPa, and a 4-spin
plaquette singlet state was recently identified in the 2 to 4GPa region [4].
We report here on high pressure (up to 2GPa), high magnetic field (up to
65T) and 3He temperature magnetostriction experiments, using FBGs. Fiber
Bragg Grating (FBG) Dilatometry [6] permits to measure the magnetostriction
of a sample in function of the response of an optical fiber to applied
strain.
[1]Continuous and discontinuous quantum phase transitions in a model
two-dimensional magnet Haravifarda S, et al., PNAS, Feb. 14, 2012 vol. 109
no. 7 2286--2289
[2] High-Resolution Study of Spin Excitations in the Singlet Ground State of
SrCu2(BO3)2, B. Gaulin, et al., Phys.Rev. Lett. 93, 267202 (2004)
[3]Quantum phase transitions in the orthogonal dimer system SrCu2.BO3.2
Hiroshi Kageyama H, et al. Physica B 329--333 (2003) 1020--1023
[4]Observation of a 4-spin Plaquette Singlet State in the
Shastry--Sutherland compound SrCu2 (BO3 )2Zayed M.E., et al. arXiv:
1603.02039v
[5]Magnetostriction and magnetic texture to 100.75 Tesla in frustrated
SrCu2(BO3)2. Proc Natl Acad Jaime M, et al. Sci US109(31)12404--12407.
(2012)
*This work was performed at the NHMFL, supported by the NSF Cooperative Agreement No. DMR-1157490 and the State of Florida, and the DOE NNSA DE-NA0001979 grant.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2017.MAR.B35.13