Title :
Low Temperature Cooling by Thermal-Field Electron Emission in a Crossed-Field Gap
Author :
Lin, Wu ; Ang, L.K.
Author_Institution :
Sch. of Electr. & Electron. Eng., Nanyang Technol. Univ., Singapore
Abstract :
A new method of refrigeration using thermal-field electron emission from nano-scale emitters of arbitrary work function in a vacuum crossed-field gap is proposed. A sample potential profile V vs. x for a sharp emitter (cathode) with effective radius R=10 nm, work function phi=4 eV, emitter-collector separation of L=20 mum, dc voltage applied at anode Vg=420 v is shown. For a given emitter (fixed work function and radius), and gap spacing, an optimal magnetic field B0 can be determined for a given electric field F at various temperatures. To achieve maximum normalized cooling power density eta, a critical electric field Fc is extracted by varying F with its corresponding B0. It is found that the optimal local cooling power density per emitter is about 600 kW/cm2 at 300 K, 2.7 kW/cm2 at 50 K and 20 W/cm2 at 10 K. To measure the efficiency of the proposed cooling method, Peltier coefficient Pi and COP = Pi/Vg at various conditions are presented. Effects of space-charge effects are also discussed
Keywords :
Peltier effect; cooling; electron field emission; refrigeration; space charge; 10 K; 300 K; 50 K; Peltier coefficient; critical electric field; crossed-field gap; gap spacing; low temperature cooling; normalized cooling power density; optimal magnetic field; refrigeration; space-charge effects; thermal-field electron emission; Anodes; Cathodes; Cooling; Density measurement; Electron emission; Magnetic fields; Refrigeration; Temperature; Time of arrival estimation; Voltage;
Conference_Titel :
Vacuum Nanoelectronics Conference, 2006 and the 2006 50th International Field Emission Symposium., IVNC/IFES 2006. Technical Digest. 19th International
Conference_Location :
Guilin
Print_ISBN :
1-4244-0401-0
DOI :
10.1109/IVNC.2006.335442