Related papers: Chiral charge as hidden order parameter in URu$_2$…
The hallmark of two-dimensional chiral topological phases is the existence of anomalous gapless modes at the spatial boundary. Yet, the manifestation of this edge anomaly within the bulk ground-state wavefunction itself remains only…
We study URu$_{2-x}$Fe$_x$Si$_2$, in which two types of staggered phases compete at low temperature as the iron concentration $x$ is varied: the nonmagnetic "hidden order" (HO) phase below the critical concentration $x_c$, and…
Since the 1985 discovery of the phase transition at $T_{\rm HO}=17.5$ K in the heavy-fermion metal URu$_2$Si$_2$, neither symmetry change in the crystal structure nor magnetic ordering have been observed, which makes this "hidden order"…
We present a perspective on the recent discoveries of possible charge ordering in underdoped Bi_2Sr_2CaCu_2O_{8+\delta} and Na_xCa_{2-x}CuO_2Cl_2 by high-resolution scanning tunnelling spectroscopy.
We present a first principles study of the ferrochiral phase transition in chiral BaTiOCu$_4$(PO$_4$)$_4$, which has been shown using X-ray diffraction to proceed via the antiferroaxial rotation of antipolar structural units. We analyze the…
We experimentally investigate the symmetry in the Hidden Order (HO) phase of intermetallic URu2Si2 by mapping the lattice and magnetic excitations via inelastic neutron and x-ray scattering measurements in the HO and high-temperature…
Charge ordering in the low-temperature triclinic structure of titanium oxide (Ti4O7) is investigated using the local density approximation (LDA)+U method. Although the total 3d charge separation is rather small, an orbital order parameter…
Chiral symmetry is a fundamental property with profound implications for the properties of elementary particles, that implies a spectral symmetry (i.e. E => -E ) in their dispersion relation. In condensed matter physics, chiral symmetry is…
We present neutron diffraction, muon spin rotation and pulsed-field magnetometry measurements on the Heisenberg quantum chiral chain [Cu(pym)(H2O)4]SiF6.H2O, which displays a four-fold-periodic rotation of the local environment around the…
We argue that the hidden order state in URu$_2$Si$_2$ will induce a charge density wave. The modulation vector of the charge density wave will be twice that of the hidden order state, $Q_{CDW} = 2Q_{HO}$. To illustrate how the charge…
Nonlinear electrical conduction primarily mediated by an orbital texture is observed in chiral semiconductor Te. We determine the enantiospecific sign of the nonlinear conductance and identify anomalies in its carrier-density dependence.…
When matter is cooled from high temperatures, collective instabilities develop amongst its constituent particles that lead to new kinds of order. An anomaly in the specific heat is a classic signature of this phenomenon. Usually the…
Charge symmetry breaking contributions to the proton's neutral weak form factors must be understood in order for future measurements of parity violating electron-proton scattering to be definitively interpreted as evidence of proton…
The conventional order parameters in quantum matters are often characterized by 'spontaneous' broken symmetries. However, sometimes the broken symmetries may blend with the invariant symmetries to lead to mysterious emergent phases. The…
Here we report a resonant x-ray diffraction (RXD) study at the Cu L3 edge on the multi-chiral system CsCuCl3, exhibiting helical magnetic order in a chiral crystal structure. RXD is a powerful technique to disentangle electronic degrees of…
Helices of increased electron density can spontaneously form in materials containing multiple, interacting density waves. Although a macroscopic order parameter theory describing this behaviour has been proposed and experimentally tested, a…
We report the observation of an emergent charge order mode in the optically-excited cuprate ladder Sr$_{14}$Cu$_{24}$O$_{41}$. Near-infrared light in the ladder plane drives a symmetry-protected electronic metastable state together with a…
Effective actions, such as nonlinear sigma models, are important tools in studying low-energy fluctuations of magnetically ordered states. Here we derive an effective action for the smooth order-parameter distortions of noncoplanar magnetic…
The term "hidden order" refers to an as yet unidentified form of broken-symmetry order parameter that is presumed to exist in the strongly correlated electron system URu2Si2 on the basis of the reported similarity of the heat capacity at…
We show that orbital currents in a CuO2 plane, if present, should be described by two independent parity and time-reversal odd order parameters, a toroidal dipole (anapole) and a magnetic quadrupole. Based on this, we derive the resonant…