The thesis discusses research on analysis of cylindrical metal clad nano-lasers. Numerical modelling of cylindrical semiconductor nano-lasers has been undertaken accommodating local gain variations in the active region of the device. Analysis is performed using the cylindrical transfer matrix method (cTMM) and the Finite Element Method (FEM). Calculations have thereby been performed of the modal gain and the lasing condition for the device supporting TE guided mode and TM Surface Plasmon Polariton (SPP) modes. For representative structures it is shown that TE and TM mode lasing can be supported in devices having cavity lengths on the order of 1μm and 60μm respectively. The methodology adopted offers means to analyse candidate semiconductor lasers. Attention is also given on structures having GaN as the material platform and utilising silver for the metal cladding. The lasing characteristics of such structures are explored for wide range of operating wavelengths and metal – cladding thicknesses. It is found that for lower order TE and TM mode lasing can be supported in devices having cavity lengths of the order of 2μm and 18μm respectively. The response of metal clad nano-lasers to direct current modulation has also been analysed in both the small signal and large signal regimes. Calculations have been performed using rate equations which include the Purcell cavity enhanced spontaneous emission factor, F, and the spontaneous emission coupling factor β. It is observed that in general increased F and β reduce the 3dB direct current modulation bandwidth. Conditions are identified where the peak modulation response occurs at frequencies 40GHz and 30 GHz can be achieved. For both small and large signal regimes modulation bandwidth of approximately 60GHz can be achieved.