Department of Physics, George Washington University, Washington, DC, United States of America.|Department of Physics, George Washington University, Washington, DC, United States of America.|Department of Physics, George Washington University, Washington, DC, United States of America.|Department of Physics, George Washington University, Washington, DC, United States of America.|Department of Physics, George Washington University, Washington, DC, United States of America.|Department of Physics, George Washington University, Washington, DC, United States of America.