Department of Electronics & Telecommunications (IET) Norwegian University of Science & Technology (NTNU) NO-7491 Trondheim, NORWAY Phone:+47 735 94409 Mobile:+47 918 97658 E-mail: helge.weman@iet.ntnu.no Office: B415 "Electro-building", Check map

Since I was appointed as a professor at NTNU in 2005 my research has focused on synthesis and characterization of semiconductor nanowires for use in energy efficient light emitters (LEDs) and solar cells. A strong focus is being made on heterostructured III-V semiconductor nanowires grown in the Molecular Beam Epitaxy (MBE) lab. Fabrication of nanowire devices is being explored by electron beam lithography, nanoimprinting and focused ion beam techniques using NTNU NanoLab. Optoelectronic characterization of single nanowires using techniques such as low temperature photoluminescence and photocurrent is done in the Nanophotonics lab. In 2012 I co-founded the start-up company CrayoNano AS who are now developing nanowire/graphene based deep-UV LEDs for sterilization and disinfection. See how nanowires can be grown on graphene in this animated YouTube video (more than 86 000 views).

NEWS!
July 2015. I am giving invited talks in Aveiro and Boston this summer.
May 12, 2015. "Rectifying Single GaAsSb Nanowire Devices Based on Self-Induced Compositional Gradients" is published in Nano Letters.
March 5 2015. Inauguration day for our new nitride III-V Veeco GEN930 MBE machine. See article in Universitetsavisa here.
July 2014. I am giving invited talks in Seoul, Dresden and Aberdeen this summer.
April 11, 2014. NTNU and IBM makes press releases related to our publication in Nature Communications.
April 10, 2014. "Inducing a direct-to-pseudodirect bandgap transition in wurtzite GaAs nanowires with uniaxial stress" is published in Nature Communications.
Jan. 27, 2014. "Position-Controlled Uniform GaAs Nanowires on Silicon using Nanoimprint Lithography" is published in Nano Letters.
June 11, 2013. An interview of me is published in Science Daily: Graphene and Semiconductor Technology Together: Smaller, Cheaper, Better.
Nov. 6, 2012. "A Story Told by a Single Nanowire: Optical Properties of Wurtzite GaAs" is published in Nano Letters.
Sept. 10, 2012. NTNU makes a press release related to our publication in Nano Letters (below) and start-up company CrayoNano.
Aug 13, 2012. "Vertically Aligned GaAs Nanowires on Graphite and Few-Layer Graphene: Generic Model and Epitaxial Growth" is published in Nano Letters.