is considerably purer than that of the blue detuned peak. From the fits to data, the visibility for the red detuned peak is around 95 % and for the blue detuned peak is around 43 %. The small change in amplitude with polariser angle is due to the slight decrease in atom number as the measurement progressed. Also from Fig. \[pol\](b), it can be seen that the shape of the blue detuned peak depends on polariser angle. The peak and the wings of the blue detuned peak seem to be oppositely polarised. This shows that the light out of the cavity for the red peak is strongly polarised and indicative of a single cavity mode present in the cavity. On the other hand, the blue detuned peak has multiple modes in coexistence, which is indicative of no mode competition and therefore is detected as a mixture of several simultaneously existing modes. The consistent explanation for this is that the light out of the cavity for the red peak is lasing. All the data mentioned above was for TEM$_{00}$ spatial mode as there are no nearby modes within the cavity linewidth which will compete with this mode. This is verified by 