Resource Type

Language

Time-resolved THz studies of carrier dynamics in semiconductors, superconductors, and strongly-correlated electron materials (open access)

Time-resolved THz studies of carrier dynamics in semiconductors, superconductors, and strongly-correlated electron materials

Perhaps the most important aspect of contemporary condensed matter physics involves understanding strong Coulomb interactions between the large number of electrons in a solid. Electronic correlations lead to the emergence of new system properties, such as metal-insulator transitions, superconductivity, magneto-resistance, Bose-Einstein condensation, the formation of excitonic gases, or the integer and fractional Quantum Hall effects. The discovery of high-Tc superconductivity in particular was a watershed event, leading to dramatic experimental and theoretical advances in the field of correlated-electron systems. Such materials often exhibit competition between the charge, lattice, spin, and orbital degrees of freedom, whose cause-effect relationships are difficult to ascertain. Experimental insight into the properties of solids is traditionally obtained by time-averaged probes, which measure e.g., linear optical spectra, electrical conduction properties, or the occupied band structure in thermal equilibrium. Many novel physical properties arise from excitations out of the ground state into energetically higher states by thermal, optical, or electrical means. This leads to fundamental interactions between the system's constituents, such as electron-phonon and electron-electron interactions, which occur on ultrafast timescales. While these interactions underlie the physical properties of solids, they are often only indirectly inferred from time-averaged measurements. Time-resolved spectroscopy, consequently, is playing an ever increasing role …
Date: November 14, 2006
Creator: Kaindl, Robert A. & Averitt, Richard D.
System: The UNT Digital Library
Chapter 4: Geological Carbon Sequestration (open access)

Chapter 4: Geological Carbon Sequestration

Carbon sequestration is the long term isolation of carbon dioxide from the atmosphere through physical, chemical, biological, or engineered processes. The largest potential reservoirs for storing carbon are the deep oceans and geological reservoirs in the earth's upper crust. This chapter focuses on geological sequestration because it appears to be the most promising large-scale approach for the 2050 timeframe. It does not discuss ocean or terrestrial sequestration. In order to achieve substantial GHG reductions, geological storage needs to be deployed at a large scale. For example, 1 Gt C/yr (3.6 Gt CO{sub 2}/yr) abatement, requires carbon capture and storage (CCS) from 600 large pulverized coal plants ({approx}1000 MW each) or 3600 injection projects at the scale of Statoil's Sleipner project. At present, global carbon emissions from coal approximate 2.5 Gt C. However, given reasonable economic and demand growth projections in a business-as-usual context, global coal emissions could account for 9 Gt C. These volumes highlight the need to develop rapidly an understanding of typical crustal response to such large projects, and the magnitude of the effort prompts certain concerns regarding implementation, efficiency, and risk of the enterprise. The key questions of subsurface engineering and surface safety associated with carbon sequestration …
Date: June 14, 2006
Creator: Friedmann, J. & Herzog, H.
System: The UNT Digital Library

Oral History Interview with Richard Vincent, March 14, 2006

Access: Use of this item is restricted to the UNT Community
Interview with Richard Vincent, a member and former pastor of the Metropolitan Community Church from Kirksville, Missouri. Vincent discusses his education and religious background, the Circle of Friends in Dallas and discovering the Metropolitan Community Church, establishing MCC Dallas, ministering to prisoners, becoming the first pastor of MCC Dallas, cooperation with bars and other LGBT community establishments, the congregation, moving the church, his theology, succeeding pastors, and reflections on his ministry.
Date: March 14, 2006
Creator: Mims, Michael & Vincent, Richard
System: The UNT Digital Library

Oral History Interview with Norvell Hill Williams Reed, September 14, 2006

Access: Use of this item is restricted to the UNT Community
Transcript of an interview with Norvell Hill Williams Reed, a longtime Denton resident and former resident of Denton's historic all-black Quakertown neighborhood. Reed shares concerning her childhood in Quakertown; family history; family's forced move out of Quakertown to Solomon Hill neighborhood of Denton; race relations in Denton; participation in Denton Christian Women's Fellowship; family's historical memories of Quakertown. Appendix includes photographs (13 pages), one map (1 page), and a list of sources (1 page).
Date: September 14, 2006
Creator: Yancey, Sherelyn & Reed, Norvell Hill Williams, 1921-
System: The UNT Digital Library

Oral History Interview with James Koger, July 14, 2006

Access: Use of this item is restricted to the UNT Community
Interview with James Koger, Army veteran, concerning his memories of childhood in Des Moines, Iowa, Peoria, Illinois, San Antonio, Texas, and Oklahoma City, Oklahoma; decision to enroll at University of Oklahoma; being drafted in 1945; training in Army Corps of Engineers; service in postwar occupation of Japan; decision to return to University of Oklahoma; career as aviation engineer with General Dynamics in Fort Worth, Texas. Appendix includes photo of interviewee.
Date: July 14, 2006
Creator: Moye, J. Todd & Koger, James
System: The UNT Digital Library

Oral History Interview with Burlyce Logan, March 14, 2006 and February 6, 2017

Access: Use of this item is restricted to the UNT Community
Interview with Burlyce Logan, one of the first African American students at North Texas, and UNT alumna whose college education began in 1956 and concluded in 2011. She recalls her childhood and education in Dallas and New York City; love of piano and musical education; decision to become one of the first African American students at North Texas; experiences as a college student, including racist incidents on campus, and as a boarder in Southeast Denton; decision to drop out in 1958; marriage to Raymond Logan, move to California, and return to Denton; decision to return to UNT as a student in 2005 and experiences on campus in the 21st century; 2011 graduation.
Date: 2006-03-14/2017-02-06
Creator: Thompson, Mark; Stallings, Chelsea & Logan, Burlyce
System: The UNT Digital Library