1821www.MaterialsViews.com wileyonlinelibrary.com detector is a detector that fi nely reacts to IR radiation, mainly including two types: thermal and photoconductive detectors. The thermal IR detectors relied on temperature dependent response, with slow response, low sensitivity but higher working temperature. [ 4 ] For the photoconductive IR detectors, the electrical signal of the detector is monitored by electronic excitations caused by the IR photons, resulting in faster response, higher sensitivity but cryogenic working temperature for reducing thermal noise. [ 5 ] In order to better keep tracking photons for photoconductive IR detectors, photoactive materials assuming a narrow bandgap are essential which would be sure to convert IR photons into electric signals with high quantum effi ciency. For narrow band-gap semiconductors (NBSs), either traditional heavy-metal-including materials like HgCdTe [ 6 ] (<0.1 eV), HgTe [ 7 ] (0-0.68 eV), or PbS quantum dots [ 8 ] (QDs) (0.4-2 eV), and so on, or heavy-metal-free materials such as MoS 2[ 9 ] (1.2 eV), In 2 Te 3 [ 10 ] (1.19 eV), semiconducting single-wall carbon nanotubes (s-SWCNTs), [ 11 ] or semiconducting graphene nanoribbons [ 12 ] et al. The hybrid structures of QDs with the conducting materials, such as SWCNT/QDs and graphene/QDs composites, further improved the capability of IR photons harvesting and detection owing to the effi cient charge separation and faster carrier mobility. [ 13 ] In the other aspect, artifi cially-designed sub-energy-level materials with smaller energy gap, which allow effective generation of IR photogenerated carriers, also attracted great attention. For example, quantum cascade IR detector, [ 14 ] GaAs based quantum well IR detectors (QWIDs). [ 15 ] However, current fabrication of ultrahigh performance photoconductive IR detectors is significantly limited by the choices of photoactive materials; nowdays, such challenges still present concerning with achieving high sensitivity and well stability at a high working temperature, as well as disposing environmental problems which come from the heavy-metal-including elements.Photoconductive IR detectors based on transition metal oxides (TMOs) have been a trigger for IR harvesting and detection for advantages as follows: easy to achieve, "green" as well as excellent stability of TMOs systems. However, TMO materials still remain an unexplored fi eld for photoconductive IR detectors with high IR response so far. Among the TMOs family, vanadium oxides offer a promising platform for photoconductive Ultrahigh Infrared Photoresponse from Core-Shell SingleDomain-VO 2 /V 2 O 5 Heterostructure in Nanobeam Zejun Li , Zhenpeng Hu , Jing Peng , Changzheng Wu ,* Yuchen Yang , Feng Feng , Peng Gao , Jinlong Yang , and ), recording the best performance compared with those reported IR detectors based on heavy-metal-free materials, and even comparable/superior to those traditional ones made from materials including heavy metals. These fi ndings pave a new way to design oxide heterostructures for int...