TY - JOUR
T1 - Confinement-deconfinement transition as an indication of spin-liquid-type behavior in Na2IrO3
AU - Alpichshev, Zhanybek
AU - Mahmood, Fahad
AU - Cao, Gang
AU - Gedik, Nuh
N1 - Publisher Copyright:
© 2015 American Physical Society.
PY - 2015/7/7
Y1 - 2015/7/7
N2 - We use ultrafast optical spectroscopy to observe binding of charged single-particle excitations (SE) in the magnetically frustrated Mott insulator Na2IrO3. Above the antiferromagnetic ordering temperature (TN) the system response is due to both Hubbard excitons (HE) and their constituent unpaired SE. The SE response becomes strongly suppressed immediately below TN. We argue that this increase in binding energy is due to a unique interplay between the frustrated Kitaev and the weak Heisenberg-type ordering term in the Hamiltonian, mediating an effective interaction between the spin-singlet SE. This interaction grows with distance causing the SE to become trapped in the HE, similar to quark confinement inside hadrons. This binding of charged particles, induced by magnetic ordering, is a result of a confinement-deconfinement transition of spin excitations. This observation provides evidence for spin liquid type behavior which is expected in Na2IrO3.
AB - We use ultrafast optical spectroscopy to observe binding of charged single-particle excitations (SE) in the magnetically frustrated Mott insulator Na2IrO3. Above the antiferromagnetic ordering temperature (TN) the system response is due to both Hubbard excitons (HE) and their constituent unpaired SE. The SE response becomes strongly suppressed immediately below TN. We argue that this increase in binding energy is due to a unique interplay between the frustrated Kitaev and the weak Heisenberg-type ordering term in the Hamiltonian, mediating an effective interaction between the spin-singlet SE. This interaction grows with distance causing the SE to become trapped in the HE, similar to quark confinement inside hadrons. This binding of charged particles, induced by magnetic ordering, is a result of a confinement-deconfinement transition of spin excitations. This observation provides evidence for spin liquid type behavior which is expected in Na2IrO3.
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U2 - 10.1103/PhysRevLett.114.017203
DO - 10.1103/PhysRevLett.114.017203
M3 - Article
AN - SCOPUS:84920971117
SN - 0031-9007
VL - 114
JO - Physical review letters
JF - Physical review letters
IS - 1
M1 - 017203
ER -