maayan yaari - Academia.edu (original) (raw)

maayan yaari

Uploads

Papers by maayan yaari

Research paper thumbnail of Adiabatic variation of the charge density wave phase diagram in the 123 cuprate (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy

Physical review, Jul 25, 2019

In order to explain the emergence of the anomalous pseudogap state and high-temperature supercond... more In order to explain the emergence of the anomalous pseudogap state and high-temperature superconductivity in the cuprates, intense research activity over three decades has focused on unravelling the connection between the various instabilities of the underdoped regime. In the high-temperature superconductor (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy (CLBLCO) isovalent chemical substitution produces smooth changes to the CuO2 plane buckling and the Cu(II)-to-apical-oxygen distance, allowing us to study the interdependence of charge-density-wave (CDW) order, superconductivity and the pseudogap at constant hole doping in two adiabatically connected representations of the 123 cuprate structure. In this study, resonant soft x-ray scattering measurements reveal the first observation of incommensurate CDW correlations in CLBLCO and demonstrate a lack of correlation between TCDW and the pseudogap crossover temperature (T *). This result disfavours a scenario in which the opening of the pseudogap at T * results from fluctuating CDW correlations.

Research paper thumbnail of Experimental determination of superexchange energy from two-hole spectra

arXiv (Cornell University), Jul 19, 2021

We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(... more We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy for x = 0.1 and x = 0.4. The spectra have contributions from band states as well as a localized multiplet structure. From their identification, we determine the intrashell Coulomb interaction U for Oxygen and Copper sites. These results allow us to estimate the atomic superexchange coupling J suggesting a positive correlation between the maximal superconducting critical temperature T max C and J.

Research paper thumbnail of Experimental determination of superexchange energy from two-hole spectra

arXiv (Cornell University), Jul 19, 2021

We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(... more We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy for x = 0.1 and x = 0.4. The spectra have contributions from band states as well as a localized multiplet structure. From their identification, we determine the intrashell Coulomb interaction U for Oxygen and Copper sites. These results allow us to estimate the atomic superexchange coupling J suggesting a positive correlation between the maximal superconducting critical temperature T max C and J.

Research paper thumbnail of Temperature changes of the Fe8 molecular magnet during its spin reversal process

Physical Review B, May 24, 2017

Tunneling of the spins in the Fe 8 molecular magnet from a metastable ground state to an excited ... more Tunneling of the spins in the Fe 8 molecular magnet from a metastable ground state to an excited state is accompanied by a decay of these spins to the global ground state and an increase of the crystal temperature. We measured this temperature using two thermometers, one strongly coupled and the other weakly coupled to the thermal bath. We found that the temperature increases to no greater than 2.2 K. This upper limit agrees with the flame temperature derived from deflagration theory and previous measurements. In light of this temperature increase we reexamine the Landau, Zener, and Stuckelberg (LZS) theory of spin tunneling in large Fe 8 crystals.

Research paper thumbnail of Adiabatic variation of the charge density wave phase diagram in the 123 cuprate (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy

Physical review, Jul 25, 2019

In order to explain the emergence of the anomalous pseudogap state and high-temperature supercond... more In order to explain the emergence of the anomalous pseudogap state and high-temperature superconductivity in the cuprates, intense research activity over three decades has focused on unravelling the connection between the various instabilities of the underdoped regime. In the high-temperature superconductor (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy (CLBLCO) isovalent chemical substitution produces smooth changes to the CuO2 plane buckling and the Cu(II)-to-apical-oxygen distance, allowing us to study the interdependence of charge-density-wave (CDW) order, superconductivity and the pseudogap at constant hole doping in two adiabatically connected representations of the 123 cuprate structure. In this study, resonant soft x-ray scattering measurements reveal the first observation of incommensurate CDW correlations in CLBLCO and demonstrate a lack of correlation between TCDW and the pseudogap crossover temperature (T *). This result disfavours a scenario in which the opening of the pseudogap at T * results from fluctuating CDW correlations.

Research paper thumbnail of Experimental determination of superexchange energy from two-hole spectra

arXiv (Cornell University), Jul 19, 2021

We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(... more We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy for x = 0.1 and x = 0.4. The spectra have contributions from band states as well as a localized multiplet structure. From their identification, we determine the intrashell Coulomb interaction U for Oxygen and Copper sites. These results allow us to estimate the atomic superexchange coupling J suggesting a positive correlation between the maximal superconducting critical temperature T max C and J.

Research paper thumbnail of Experimental determination of superexchange energy from two-hole spectra

arXiv (Cornell University), Jul 19, 2021

We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(... more We follow the evolution of Copper and Oxygen two-hole excitations, in optimally doped (CaxLa1−x)(Ba1.75−xLa0.25+x)Cu3Oy for x = 0.1 and x = 0.4. The spectra have contributions from band states as well as a localized multiplet structure. From their identification, we determine the intrashell Coulomb interaction U for Oxygen and Copper sites. These results allow us to estimate the atomic superexchange coupling J suggesting a positive correlation between the maximal superconducting critical temperature T max C and J.

Research paper thumbnail of Temperature changes of the Fe8 molecular magnet during its spin reversal process

Physical Review B, May 24, 2017

Tunneling of the spins in the Fe 8 molecular magnet from a metastable ground state to an excited ... more Tunneling of the spins in the Fe 8 molecular magnet from a metastable ground state to an excited state is accompanied by a decay of these spins to the global ground state and an increase of the crystal temperature. We measured this temperature using two thermometers, one strongly coupled and the other weakly coupled to the thermal bath. We found that the temperature increases to no greater than 2.2 K. This upper limit agrees with the flame temperature derived from deflagration theory and previous measurements. In light of this temperature increase we reexamine the Landau, Zener, and Stuckelberg (LZS) theory of spin tunneling in large Fe 8 crystals.

Log In