@misc{kolorenc_mitas_2011, title={Applications of quantum Monte Carlo methods in condensed systems}, volume={74}, ISSN={["1361-6633"]}, DOI={10.1088/0034-4885/74/2/026502}, abstractNote={Quantum Monte Carlo methods represent a powerful and broadly applicable computational tool for finding very accurate solutions of the stationary Schrödinger equation for atoms, molecules, solids and a variety of model systems. The algorithms are intrinsically parallel and are able to take full advantage of present-day high-performance computing systems. This review paper concentrates on the fixed-node/fixed-phase diffusion Monte Carlo method with emphasis on its applications to the electronic structure of solids and other extended many-particle systems.}, number={2}, journal={REPORTS ON PROGRESS IN PHYSICS}, author={Kolorenc, Jindrich and Mitas, Lubos}, year={2011}, month={Feb} }
 @article{li_kolorenc_mitas_2011, title={Atomic Fermi gas in the unitary limit by quantum Monte Carlo methods: Effects of the interaction range}, volume={84}, ISSN={["1094-1622"]}, DOI={10.1103/physreva.84.023615}, abstractNote={We calculate the ground-state properties of an unpolarized two-component Fermi gas with the aid of the diffusion quantum Monte Carlo (DMC) methods. Using an extrapolation to the zero effective range of the attractive two-particle interaction, we find E/E{sub free} in the unitary limit to be 0.212(2), 0.407(2), 0.409(3), and 0.398(3) for 4, 14, 38, and 66 atoms, respectively. Our calculations indicate that the dependence of the total energy on the effective range of the interaction R{sub eff} is sizable and the extrapolation to R{sub eff}=0 is therefore important for reaching the true unitary limit. To test the quality of nodal surfaces and to estimate the impact of the fixed-node approximation, we perform released-node DMC calculations for 4 and 14 atoms. Analysis of the released-node and the fixed-node results suggests that the main sources of the fixed-node errors are long-range correlations, which are difficult to sample in the released-node approaches due to the fast growth of the bosonic noise. Besides energies, we evaluate the two-body density matrix and the condensate fraction. We find that the condensate fraction for the 66-atom system converges to 0.56(1) after the extrapolation to the zero interaction range.}, number={2}, journal={PHYSICAL REVIEW A}, author={Li, Xin and Kolorenc, Jindrich and Mitas, Lubos}, year={2011}, month={Aug} }
 @article{kolorenc_mitas_2010, title={Electronic structure of solid FeO at high pressures by quantum Monte Carlo methods}, volume={3}, ISSN={["1875-3892"]}, DOI={10.1016/j.phpro.2010.01.203}, abstractNote={Abstract We determine equation of state of stoichiometric FeO by employing the diffusion Monte Carlo method. The fermionic nodes of the many-body wave function are fixed by a single Slater determinant of one-particle orbitals extracted from spin-unrestricted Kohn–Sham equations utilizing a hybrid exchange-correlation functional. The calculated ambient pressure properties agree very well with available experimental data. At approximately 65 GPa, the atomic lattice is found to change from the rocksalt B1 to the NiAs-type inverse B8 structure.}, number={3}, journal={PROCEEDINGS OF THE 22TH WORKSHOP ON COMPUTER SIMULATION STUDIES IN CONDENSED MATTER PHYSICS (CSP 2009)}, author={Kolorenc, Jindrich and Mitas, Lubos}, year={2010}, pages={1437–1441} }
 @article{kolorenc_hu_mitas_2010, title={Wave functions for quantum Monte Carlo calculations in solids: Orbitals from density functional theory with hybrid exchange-correlation functionals}, volume={82}, ISSN={["1098-0121"]}, DOI={10.1103/physrevb.82.115108}, abstractNote={We investigate how the fixed-node diffusion Monte Carlo energy of solids depends on single-particle orbitals used in Slater--Jastrow wave functions. We demonstrate that the dependence can be significant, in particular in the case of 3d transition-metal compounds, which we adopt as examples. We illustrate how exchange-correlation functionals with variable exact-exchange component can be exploited to reduce the fixed-node errors. On the basis of these results we argue that the fixed-node quantum Monte Carlo provides a variational approach for optimization of effective hamiltonians with parameters.}, number={11}, journal={PHYSICAL REVIEW B}, author={Kolorenc, Jindrich and Hu, Shuming and Mitas, Lubos}, year={2010}, month={Sep} }
 @article{shick_kolorenc_lichtenstein_havela_2009, title={Electronic structure and spectral properties of Am, Cm, and Bk: Charge-density self-consistent LDA plus HIA calculations in the FP-LAPW basis}, volume={80}, number={8}, journal={Physical Review. B, Condensed Matter and Materials Physics}, author={Shick, A. B. and Kolorenc, J. and Lichtenstein, A. I. and Havela, L.}, year={2009} }
 @article{kolorenc_mitas_2008, title={Quantum Monte Carlo calculations of structural properties of FeO under pressure}, volume={101}, number={18}, journal={Physical Review Letters}, author={Kolorenc, J. and Mitas, L.}, year={2008} }
 @article{kolorenc_mitas_2007, title={B1-to-B8 structural phase transition in MnO under pressure: Comparison of all-electron and pseudopotential approaches}, volume={75}, ISSN={["2469-9969"]}, DOI={10.1103/physrevb.75.235118}, abstractNote={We employ the density-functional theory to study a structural transition of MnO from B1 rocksalt to B8 NiAs structures that was observed experimentally at pressures around 100 GPa. We utilize all-electron description as well as norm-conserving pseudopotentials and demonstrate that these two approaches can significantly differ in quantitative predictions. We explicitly show that even small-core pseudopotentials exhibit transferability inaccuracies for quantities sensitive to the energy differences between high- and low-spin polarizations of valence electrons.}, number={23}, journal={PHYSICAL REVIEW B}, author={Kolorenc, Jindrich and Mitas, Lubos}, year={2007}, month={Jun} }
 @article{shick_kolorenc_havela_drchal_gouder_2007, title={Multiplet effects in the electronic structure of delta-Pu, Am and their compounds}, volume={77}, number={1}, journal={Europhysics Letters}, author={Shick, A. and Kolorenc, J. and Havela, L. and Drchal, V. and Gouder, T.}, year={2007} }