June 22, 2020

Our paper exploring the field dependence of the spin excitations and the formation of static order in NaYbO2 was published today in Phys. Rev. B.  This work reveals a first order phase boundary out of the field induced up-up-down state in this quantum spin liquid candidate system.  We further explore the crystal field Hamiltonian as well as the spin dynamics of the field-induced ordered state in this material.

The paper can be found here: Physical Review B

May 15, 2020

Our paper exploring the effect of magnetic field on the magnetism of the Weyl seimetal candidate Eu1-xSmxTiO3 was published in Physical Review Materials today.  This paper using neutron diffraction to correlate the preivously reported anomalous magnetotransport in this system to a field-induced spin-flop transition.

The paper can be found here:  Physical Review Materials

May 14, 2020

Our paper reporting the discovery of the first three-magnon bound state in an antiferromagnet was published today in Physical Review Letters.  This work shows that unusual quantum effects such as few-body bound states arise in the triangular lattice of classical spins in NaMnO2.  The dimensional frustration in this material yields one dimensional bound states of magnons.

The paper can be found here:  Physical Review Letters

August 09, 2019

Our paper exploring the evolution of the electronic ground state of Nd2Ir2O7 when doped with hole (via Ca substitution) was published today.  This study demonstrates the coincident suppression of long-range iridium magnetism with the closing of the charge gap.  Our work provides a guide for future studies looking to explore carrier-induced quantum critical points in this material.

Physical Review B

July 29, 2019

Our paper was published today reporting the discovery of a novel, field tunable quantum disordered magnetic state in NaYbO2.  Our results suggest a Dirac spin liquid state forms in this material whose degeneracy can be broken and driven into an intermediate "up-up-down" antiferromagnetic state via the application of a magnetic field.  It suggests an exciting new frontier of exploring the critical phase boundary between a quantum spin liquid and antiferromagnetically ordered state. 

April 22, 2019

Our paper detailing the high pressure floating zone furnace created in our lab was published today in the journal Review of Scientific Instruments.  This furnace is capable of floating zone growth at world leading growth pressures and is the culmination of a multiyear development effort supported by the W. M. Keck Foundation.  The furnace opens up a new frontier for the growth of ultrahigh purity quantum materials preciously inaccessible to the floating zone technique due to their volatility or decomposition at lower pressures.

April 17, 2019

Our paper exploring the electronic ground state in Sr3IrRuO7 was published today in Physical Review Letters.  Our multimodal exploration of this compound unveiled an unusual strange metal state prior to the complete collapse the spin-orbit Mott phase endemic to Sr3Ir2O7.  An incoherent Fermi surface and magnon spectrum appear, despite the presence of long-range antiferromagnetism, and are proposed to be indicative of strong spin-charge coupling in this material.

April 12, 2019

Congratulations to Julia for receiving the NSF Graduate Research Fellowship (NSF-GRF)!  


March 13, 2019

Our paper exploring the effect of transition metal ion substitution in the Jeff=1/2 Mott insulator Sr3Ir2O7 was published in J. Phys. Cond Matt.  Here combined neutron and resonant x-ray scattering studies revealed an unusual suppression of the Ir order upon 3d  Mn substitution, while Mn spin order persists across the entire phase diagram.  This reveals an unusual percolation  mechanism that differs between the 5d and 3d cations and likely arises due to extended exchange on the 3d Mn sublattice.

November 01, 2018

Our paper exploring the evolution of static order in NaMnO2 was published today.  This paper explores the evolution of quasi-1D correlations in this material as it cools toward the ordered state.  An intermediate, incommensurate order is observed prior to the freezing of three dimensional Neel order.  This is consistent with expectations of a mean-field model of weakly coupled Ising chains.  

Physical Review B

October 16, 2018

Our paper reporting the synthesis of Sr3Ir2O7F2 appeared today.  This work shows that F anions intercalate readily into the bilayer spin-orbit Mott insulator Sr3Ir2O7 and can completely oxidize Ir cations from Ir4+ to Ir5+.  In doing so, they generate a novel spin-orbit driven band insulating phase.  This opens up the investigation of hole-doping the Jeff=1/2 Mott state of Sr3Ir2O7 and searching for emergent states once the charge gap collapses.

Physical Review B

September 06, 2018

Our paper exploring charge and orbital texture in SmTiO3/SrTiO3 quantum well heterostructures appeared today in Physical Review Materials.  This work resolves the formation and depth profile of Ti3+d quantum well charge states embedded within the Ti3+ Mott matrix of SmTiO3 in the monolayer, quantum well limit.  Resonant x-ray reflectometry is shown to be a powerful tool for studying charge and orbital textures within quantum critical Mott/band insulating heterostructures.

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June 11, 2018

Our paper studies the unusual magnetism of NaMnO2 was published in Nature Communications.  This work established that the strong Jahn-Teller distortion in this system renormalizes the interactions of the triangular spin lattice to be quasi-one dimensional, and the accompanying uniaxial single-ion anisotropy creates an Ising-like anisotropy in the system.  The result is a spin system where magnons have a strong binding energy, creating a rare example of a stable spin amplitude mode.

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April 09, 2018

Graduate student Rebecca Dally recently received a highly competitive postdoctoral fellowship from the National Research Council.  She will be performing research at the NIST Center for Neutron Research and will begin in Aug. 2018.  Congratulations Rebecca!

April 09, 2018

Michael Aling, an undergraduate working in the group, was recently awarded the prestigious Barry Goldwater scholarship.  This highly competitive award was awarded to only ~200 students nationwide and only 40 engineering students.  Congratulations Michael!

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April 02, 2018

Our paper exploring the effect of octaheral tilts on the ferrimagnetic groundstate of GdTiO3 appeared in Applied Physics Letters.  In this paper, we resolve that the ferrimagnetic ground state of GdTiO3 remains suprisingly robust despite a substantial renormalization of the t2g bandwidth due to the interface driven relaxation of the octahedral tilts.  Our work points toward the formation of magnetic deadlayers at interfaces that account for the apparent reduction in magnetization as the GdTiO3 layers are thinned.

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March 26, 2018

Our paper exploring the magnetocaloric response of the skyrmion host FeGe appeared today in Physical Review B.  This study develops a high throughput technique for identifying subtle thermodynamic phase boundaries in skyrmion hosts and more generally in complex (H,T) phase diagrams.  We use FeGe as a case study to illustrate the presence of a first order line of  Brazovskii transitions and a single skyrmion pocket within its magnetic phase diagram.

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February 20, 2018

Our paper exploring heterostructures comprised of SrTiO3 quantum wells embedded within an SmTiO3 Mott matrix was published.  By using a combination of low energy muon relaxation measurements with polarized neutron reflectometry, we uncovered a the formation of incipient antiferromagentism in the quantum wells coincident with pseudogap formation and quantum critical magnetotransport.  This suggests that the essential physics of pseudogap states in bulk transition metal oxides can be captured in this highly controlled thin film architecture.  

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January 09, 2018

Our paper appeared today unveiling a unidirectional spin density wave state in electron-doped Sr2IrO4. Resonant x-ray scattering experiments were able to detect a spin modulation that forms along the Ir-Ir bond diagonal in this system once a coherent Fermi surface is established.  This forms an electronically phase separated state that mirrors the magnetic state observed in hole-doped high-Tc cuprates at very low doping levels. 

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November 18, 2017

Rebecca Dally was recently awarded the American Physical Society’s GMAG Dissertation Award for her work exploring magnetism in a series of transition metal oxides with intertwined spin and orbital degrees of freedom.  GMAG is the APS topical group focusing on magnetism and the award carries with it a cash prize as well as an invited talk at the annual March Meeting of the American Physical Society which is located in Los Angeles in 2018.  Congratulations Rebecca!

October 15, 2017

Graduate student in the group Ryan Need recently received a postdoctoral fellowship award from the National Research Council to perform work at the NIST Center for Neutron Research.  The highly competitive fellowship has an initial appointment term of two years, and Ryan will begin in Feb. 2018.  Congratulations Ryan!

July 28, 2017

Our paper reviewing high purity, active crystal growth techniques for quantum materials synthesis was published.  This is a brief topical review of bulk crystal growth techniques that allow for active tuning and monitoring of crystallization during crystal growth, and examples are provided highlighting the importance of these techniques in advancing our understanding of forefront quantum materials.  

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June 13, 2017

Our work exploring the structural response of (Sr1-xLax)3Ir2O7 to electron doping was published in Physical Review B.  This paper resolves a structural symmetry lowering from C2/c to P21/c below a critical temperature that grows with increased La substitution.  This distortion creates two unique iridium sites within the IrO6 bilayers of this material and is a secondary structural response to the onset of the proposed charge order in this system.

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January 15, 2017

Our paper detailing the means of producing large volume, high purity crystals of α-Na0.90MnO2 appeared.  The floating zone growth of this system opens up a number of new research avenues for exploring this correlated cathode material.

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November 09, 2016

Our paper exploring the evolution of the structural and electronic phases of (Sr1-xCax)2IrO4 appeared today in Physical Review B.  This study unveiled the effect of chemical pressure on the structural stability, magnetism, and insulating ground state of the spin-orbit Mott insulator Sr2IrO4.  A series of distinct structure types appear with increasing Ca-content, each suggestive of reduced electronic dimensionality and are potential hosts of unconventional magnetism.

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