[1] Harvard Univ, Sch Engn & Appl Sci, Cambridge, MA 02138 USA
[2] Texas A&M Univ, Inst Quantum Studies, College Stn, TX 77843 USA
[3] Texas A&M Univ, Dept Phys, College Stn, TX 77843 USA
[4] Univ Politecn Marche, Dipartimento Fis & Ingn Mat & Terr, I-60131 Ancona, Italy
[5] Singapore Inst Mfg Technol, Singapore 638075, Singapore
[6] Univ Trento, Dipartimento Fis, I-38100 Trento, Italy