A thermally tunable laser includes: a substrate; a laser resonator, wherein the laser resonator includes a gain section, and wherein the laser resonator includes a tuning section; a heating arrangement; a heat sink arrangement for dissipating a heat flow from the laser resonator to the heat sink arrangement; and a hole arrangement for influencing the heat flow from the laser resonator to the heat sink arrangement, wherein the hole arrangement is arranged between the substrate and the heat sink arrangement, wherein one or more holes of the hole arrangement include at least one hole being arranged within a horizontal range of the tuning section, so that a thermal resistance between the tuning section and the heat sink arrangement is increased.