Paula Liliana Giraldo Gallo

This project intends to determine the universal characteristics of a charge density wave quantum critical point (QCP) in the electronic phase diagram of materials. A QCP marks the point in a phase diagram of temperature-tuning parameter at which a phase transition in a material is realized at zero temperature. This project will combine material synthesis (producing compounds of the highest quality possible, in the form of single crystals, and with the possibility of designing the chemical composition of the produced materials), basic characterization through a variety of experimental techniques (X-ray diffraction, chemical composition characterization, microscopy characterization, electrical transport, magnetic and thermodynamic measurements), advanced characterization through state of the art experimental tools to unravel the nature of phase transitions (Resonant Ultrasound Spectroscopy - RUS), and measurements under extreme conditions (ultra-high magnetic fields and low temperatures), in order to establish the universal characteristics of  quantum criticality associated with charge density wave ordering, and its relation with the optimization of novel electronic properties in compounds. I plan to start by exploring the following families of CDW materials: Transition metal chalcogenides (quasi-2D dichalcogenides, MX2, and quasi 1-D chalcogenides, such as MX3or MX4), bismuthate superconductors (Ba1-xKxBiO3and related) and transition metal oxide bronzes (AxMO3). In addition, this project intends to answer the same questions for the purely 2D and 1D limit in the transition metal chalcogenides family, by obtaining few-atomic layer samples and studying how their electronic properties are modified compared to the bulk samples.

This project intends to determine the universal characteristics of a charge density wave quantum critical point (QCP) in the electronic phase diagram of materials. A QCP marks the point in a phase diagram of temperature-tuning parameter at which a phase transition in a material is realized at zero temperature. This project will combine material synthesis (producing compounds of the highest quality possible, in the form of single crystals, and with the possibility of designing the chemical composition of the produced materials), basic characterization through a variety of experimental techniques (X-ray diffraction, chemical composition characterization, microscopy characterization, electrical transport, magnetic and thermodynamic measurements), advanced characterization through state of the art experimental tools to unravel the nature of phase transitions (Resonant Ultrasound Spectroscopy - RUS), and measurements under extreme conditions (ultra-high magnetic fields and low temperatures), in order to establish the universal characteristics of  quantum criticality associated with charge density wave ordering, and its relation with the optimization of novel electronic properties in compounds. I plan to start by exploring the following families of CDW materials: Transition metal chalcogenides (quasi-2D dichalcogenides, MX2, and quasi 1-D chalcogenides, such as MX3or MX4), bismuthate superconductors (Ba1-xKxBiO3and related) and transition metal oxide bronzes (AxMO3). In addition, this project intends to answer the same questions for the purely 2D and 1D limit in the transition metal chalcogenides family, by obtaining few-atomic layer samples and studying how their electronic properties are modified compared to the bulk samples.