Low frequency noise and photo-enhanced field emission from ultrathin PbBiSe nanosheets

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2016-01, Vol.4 (5), p.196-113
• Main Authors: Suryawanshi, Sachin R, Guin, Satya N, Chatterjee, Arindom, Kashid, Vikas, More, Mahendra A, Late, Dattatray J, Biswas, Kanishka
• Format: Article
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/c5tc02993g

Atomically thin two-dimensional layered materials have gained wide interest owing to their novel properties and potential for applications in nanoelectronic and optoelectronic devices. Here, we present the spectral analysis and photo-enhanced field emission studies of a layered intergrowth PbBi 2 Se 4 nanosheet emitter, performed at the base pressure of ∼1 × 10 −8 mbar. The emitter shows a turn-on field value of ∼4.80 V μm −1 , corresponding to an emission current density of ∼1 μA cm −2 . Interestingly, when the cathode was illuminated with visible light, it exhibited a lower turn-on field of ∼3.90 V μm −1 , and a maximum emission current density of ∼893 μA cm −2 has been drawn at an applied electric field of ∼8.40 V μm −1 . Furthermore, the photo-enhanced emission current showed reproducible, step-like switching behavior in synchronous with ON-OFF switching of the illumination source. The emission current-time plots reveal excellent stability over a duration of ∼6 h. Low-frequency noise is a significant limitation for the performance of nanoscale electronic devices. The spectral analysis performed on a Fast Fourier Transform (FFT) analyzer revealed that the observed noise is of 1/ f α type, with the value of α ∼0.99. The low frequency noise, photo-enhanced field emission, and reproducible switching behavior characterized with very fast rise and fall times propose the layered PbBi 2 Se 4 nanosheet emitter as a new promising candidate for novel vacuum nano-optoelectronic devices. PbBi 2 Se 4 nanosheets demonstrate high performance and extremely stable photosensitive field emission with low frequency noise.