Many-Body Localization and the Emergence of Quantum Darwinism

Quantum Darwinism (QD) is the process responsible for the proliferation of redundant information in the environment of a quantum system that is being decohered. This enables independent observers to access separate environmental fragments and reach consensus about the system’s state. In this work, we study the effect of disorder in the emergence of QD and find that a highly disordered environment is greatly beneficial for it. By introducing the notion of lack of redundancy to quantify objectivity, we show that it behaves analogously to the entanglement entropy (EE) of the environmental eigenstate taken as an initial state. This allows us to estimate the many-body mobility edge by means of our Darwinistic measure, implicating the existence of a critical degree of disorder beyond which the degree of objectivity rises the larger the environment is. The latter hints the key role that disorder may play when the environment is of a thermodynamic size. At last, we show that a highly disordered evolution may reduce the spoiling of redundancy in the presence of intra-environment interactions.

Tuning Valley Degeneracy with Band Inversion

Valley degeneracy is a key feature of the electronic structure that benefits the thermoelectric performance of a material. Despite recent studies which claim that high valley degeneracy can be achieved with inverted bands, our survey of rock-salt IV-VI compounds demonstrates that mere band inversion is an insufficient condition for high valley degeneracy; rather, there is a critical degree to which the bands must be inverted to induce multiple carrier pockets. The so-called “band inversion parameter” is a chemically-tunable parameter, offering a design route to achieving high valley degeneracy in compounds with inverted bands. We predict that the valley degeneracy of rock-salt IV-VI compounds can be increased from NV = 4 to NV = 24, which could result in a corresponding increase in the thermoelectric figure of merit zT.

An Investigation on the Critical Degree of Saturation of Half Brick Samples via the Frost Dilatometry Methodology

An Investigation on the Critical Degree of Saturation of Half Brick Samples via the Frost Dilatometry Methodology By Javeriya Hasan Master of Building Science in the Program of Building Science 2019 An assessment of freeze-thaw deterioration of bricks necessitates predicting the moisture content at which frost decay occurs, whereby this is called the critical degree of saturation (Scrit). The study involved performing frost dilatometry testing of eight half-brick samples. Strains along the x, y and z axes of samples were measured, whereby the results show that trends of frost decay were non-uniform along certain axes. However, along the z-axis, brick sample types 305-EB4, 295AF4, 297-EB2 showed Scrit values of 81%, 90% and 77.5% respectively, which were comparable to the slices’ Scrit, which were at 84.4%, 88.1% and 77.5% respectively. Similarly, for brick sample type 349-ER1, the Scrit at its x-axis was 92%, which was near to its slice’s Scrit, at 87.3%. Sample types 60 and 295-F2 showed differences as high as 17% in their Scrit values, at 56% and 88% respectively, compared to their slices, which were at 73.4% and 78.4%.

An Investigation on the Critical Degree of Saturation of Half Brick Samples via the Frost Dilatometry Methodology

An Investigation on the Critical Degree of Saturation of Half Brick Samples via the Frost Dilatometry Methodology By Javeriya Hasan Master of Building Science in the Program of Building Science 2019 An assessment of freeze-thaw deterioration of bricks necessitates predicting the moisture content at which frost decay occurs, whereby this is called the critical degree of saturation (Scrit). The study involved performing frost dilatometry testing of eight half-brick samples. Strains along the x, y and z axes of samples were measured, whereby the results show that trends of frost decay were non-uniform along certain axes. However, along the z-axis, brick sample types 305-EB4, 295AF4, 297-EB2 showed Scrit values of 81%, 90% and 77.5% respectively, which were comparable to the slices’ Scrit, which were at 84.4%, 88.1% and 77.5% respectively. Similarly, for brick sample type 349-ER1, the Scrit at its x-axis was 92%, which was near to its slice’s Scrit, at 87.3%. Sample types 60 and 295-F2 showed differences as high as 17% in their Scrit values, at 56% and 88% respectively, compared to their slices, which were at 73.4% and 78.4%.