Quasitwodimensional BoseEinstein condensation of spin triplets in the dimerized quantum magnet ${\mathrm{Ba}}_{2}{\mathrm{CuSi}}_{2}{\mathrm{O}}_{6}{\mathrm{Cl}}_{2}$
Abstract
We synthesized single crystals of composition Ba_{2}CuSi_{2}O_{6}Cl_{2} and investigated their quantum magnetic properties. The crystal structure is closely related to that of the quasitwodimensional (2D) dimerized magnet BaCuSi_{2}O_{6} also known as Han purple. Ba_{2}CuSi_{2}O_{6}Cl_{2} has a singlet ground state with an excitation gap of Δ/k_{B} = 20.8 K. The magnetization curves for two different field directions almost perfectly coincide when normalized by the g factor except for a small jump anomaly for a magnetic field perpendicular to the c axis. The magnetization curve with a nonlinear slope above the critical field is in excellent agreement with exactdiagonalization calculations based on a 2D coupled spindimer model. Individual exchange constants are also evaluated using density functional theory (DFT). The DFT results demonstrate a 2D exchange network and weak frustration between interdimer exchange interactions, supported by weak spinlattice coupling implied from our magnetostriction data. Lastly, the magneticfieldinduced spin ordering in Ba_{2}CuSi_{2}O_{6}Cl_{2} is described as the quasi2D BoseEinstein condensation of triplets.
 Authors:

 Tokyo Institute of Technology, Tokyo (Japan)
 Univ. of Tokyo, Chiba (Japan)
 IFW Dresden, Dresden (Germany); Technical Univ. Dresden, Dresden (Germany)
 Ehime Univ., Ehime (Japan)
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sorbonne Univ., Univ. Pierre et Marie Curie  Paris 6, Paris (France)
 AixMarseille Univ., Marseille Cedex 9 (France)
 Publication Date:
 Research Org.:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1343717
 Alternate Identifier(s):
 OSTI ID: 1325607
 Report Number(s):
 LAUR1628415
Journal ID: ISSN 24699950; PRBMDO; TRN: US1701625
 Grant/Contract Number:
 AC5206NA25396
 Resource Type:
 Accepted Manuscript
 Journal Name:
 Physical Review B
 Additional Journal Information:
 Journal Volume: 94; Journal Issue: 9; Journal ID: ISSN 24699950
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; High Magnetic Field Science
Citation Formats
Okada, Makiko, Tanaka, Hidekazu, Kurita, Nobuyuki, Johmoto, Kohei, Uekusa, Hidehiro, Miyake, Atsushi, Tokunaga, Masashi, Nishimoto, Satoshi, Nakamura, Masaaki, Jaime, Marcelo, Radtke, Guillaume, and Saul, Andres. Quasitwodimensional BoseEinstein condensation of spin triplets in the dimerized quantum magnet Ba2CuSi2O6Cl2. United States: N. p., 2016.
Web. doi:10.1103/PhysRevB.94.094421.
Okada, Makiko, Tanaka, Hidekazu, Kurita, Nobuyuki, Johmoto, Kohei, Uekusa, Hidehiro, Miyake, Atsushi, Tokunaga, Masashi, Nishimoto, Satoshi, Nakamura, Masaaki, Jaime, Marcelo, Radtke, Guillaume, & Saul, Andres. Quasitwodimensional BoseEinstein condensation of spin triplets in the dimerized quantum magnet Ba2CuSi2O6Cl2. United States. doi:10.1103/PhysRevB.94.094421.
Okada, Makiko, Tanaka, Hidekazu, Kurita, Nobuyuki, Johmoto, Kohei, Uekusa, Hidehiro, Miyake, Atsushi, Tokunaga, Masashi, Nishimoto, Satoshi, Nakamura, Masaaki, Jaime, Marcelo, Radtke, Guillaume, and Saul, Andres. Tue .
"Quasitwodimensional BoseEinstein condensation of spin triplets in the dimerized quantum magnet Ba2CuSi2O6Cl2". United States. doi:10.1103/PhysRevB.94.094421. https://www.osti.gov/servlets/purl/1343717.
@article{osti_1343717,
title = {Quasitwodimensional BoseEinstein condensation of spin triplets in the dimerized quantum magnet Ba2CuSi2O6Cl2},
author = {Okada, Makiko and Tanaka, Hidekazu and Kurita, Nobuyuki and Johmoto, Kohei and Uekusa, Hidehiro and Miyake, Atsushi and Tokunaga, Masashi and Nishimoto, Satoshi and Nakamura, Masaaki and Jaime, Marcelo and Radtke, Guillaume and Saul, Andres},
abstractNote = {We synthesized single crystals of composition Ba2CuSi2O6Cl2 and investigated their quantum magnetic properties. The crystal structure is closely related to that of the quasitwodimensional (2D) dimerized magnet BaCuSi2O6 also known as Han purple. Ba2CuSi2O6Cl2 has a singlet ground state with an excitation gap of Δ/kB = 20.8 K. The magnetization curves for two different field directions almost perfectly coincide when normalized by the g factor except for a small jump anomaly for a magnetic field perpendicular to the c axis. The magnetization curve with a nonlinear slope above the critical field is in excellent agreement with exactdiagonalization calculations based on a 2D coupled spindimer model. Individual exchange constants are also evaluated using density functional theory (DFT). The DFT results demonstrate a 2D exchange network and weak frustration between interdimer exchange interactions, supported by weak spinlattice coupling implied from our magnetostriction data. Lastly, the magneticfieldinduced spin ordering in Ba2CuSi2O6Cl2 is described as the quasi2D BoseEinstein condensation of triplets.},
doi = {10.1103/PhysRevB.94.094421},
journal = {Physical Review B},
number = 9,
volume = 94,
place = {United States},
year = {2016},
month = {9}
}
Web of Science
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