Charge Modulations in the Superconducting State of the Cuprates

Motivated by the recent scanning tunneling microscopy (STM) and neutron scattering experiments, we investigate various charge density wave orders coexisting with superconductivity in the cuprate superconductors. The explicit expressions of the local density of states and its Fourier component at the ordering wavevector for the weak charge modulations are derived. It is shown that the STM experiments in $Bi_2Sr_2CaCu_2O_{8+\delta}$ cannot be explained by a site- or bond-centered charge modulation alone, but agree well with the presence of the dimerization hopping and transverse pairing modulations. We also calculate the spectral function for the charged stripes, which is measured by the ARPES experiments.Comment: 3 pages with 4 figures. To be published in PR

A Computationally Efficient Method for Accurate Spectral Testing without Requiring Coherent Sampling

The Fast Fourier Transform is the ubiquitous method of choice for spectral testing. However, its correct application to periodic signals requires either strict coherent sampling, or careful windowing, or other techniques that are computationally inefficient. This paper introduces a new method for achieving accurate spectral testing for periodic signals without the need for coherent sampling or windowing. Furthermore the method is computationally very efficient with only minimal addition to the computational complexity of FFT. The method is validated with both simulation data and experimental data. Extensive controlled simulation indicates that the method is very robust to errors in signal frequency, phase, amplitude, additive noise, and so on. Statistical analysis and comparative studies demonstrate that the proposed method achieves spectral testing accuracies similar to those obtained with perfect coherent sampling in an ideal noise-free environment. 1

Self-templated pseudomorphic transformation of ZIF into layered double hydroxides for improved supercapacitive performance

Self-templated pseudomorphic transformation of ZIF into layered double hydroxides for improved supercapacitive performanc

Genetic Admixture in the Culturally Unique Peranakan Chinese Population in Southeast Asia

10.1093/molbev/msab187Molecular Biology and Evolution38104463-447