Apr. 2001 – Mar. 2005
Advanced Telecommunications Research Institute International (ATR)
(Received founding anniversary award in 2004 from ATR for his contribution to the development of two-dimensional microcavity lasers)

Nov. 2007 – Jun. 2008
Advanced Telecommunications Research Institute International

Sep. 2010 – Feb. 2011
NTT Communication Science Laboratories

Aug. 2012 – Feb. 2013
NTT Communication Science Laboratories

Aug. 2013 – Feb. 2014
NTT Communication Science Laboratories　and　Kanazawa University

Jun. 2014 – Feb. 2015
NTT Communication Science Laboratories,　Kanazawa University, and　Waseda University