WORKING:

• When a DC bias of value equal or more than threshold field (of about 3.3KV/cm) is applied to an n-type GaAs sample, the charge density and electric field within the sample become nonuniform creating domains that is electron in some region of the sample will be first to experience the inter valley transfer than the rest of the electrons in the sample.
• The EF inside the dipole domain will be greater than the fields on either side of the dipole so the electrons in that region or domain will move to upper- valley and hence with less mobility.
• This creates a slight deficiency of e-1 s in the region immediately ahead. This region of excess and efficient e-1 s form a dipole layer.
• As the dipole drifts along more e-1 s in the vicinity will be transferred to the U-valley until the electric field outside the dipole region is depress below the threshold EF.
• This dipole continues towards the anode until it is collected upon collector, the EF in the sample jumps immediately to its original value and next domain formation begins as soon as the field values exceeds the threshold values and this process is repeated cyclically.