The transition metal dichalcogenide PdTe2 was recently shown to be a unique system where a type II Dirac semimetallic phase and a superconducting phase co-exist. This observation has led to wide speculation on the possibility of the emergence of an unconventional topological superconducting phase in PdTe2. Here, through direct measurement of the superconducting energy gap by scanning tunneling spectroscopy (STS), and temperature and magnetic field evolution of the same, we show that the superconducting phase in PdTe2 is conventional in nature. The superconducting energy gap is measured to be 326 µeV at 0.38 K and it follows a temperature dependence that is well described within the framework of Bardeen-Cooper-Schriefer's (BCS) theory of conventional superconductivity. This is surprising because our quantum oscillation measurements confirm that at least one of the bands participating in transport has topologically non-trivial character.It is believed that a superconducting ground state realized on a material displaying topologically non-trivial character might lead to the discovery of the elusive phase of matter called topological superconductivity 1-3 where relativistic Majorana fermions could emerge as excitations. 4-10 In the past, attempts were made to realize such a phase of matter through a number of ways, like, doping a topological insulator, 11-13 applying pressure on topological systems, 14 fabricating proximity-coupled heterostructures of topological insulators and conventional superconductors, 10,15 making mesoscopically confined point contacts on topological crystalline insulator, 16 Dirac 17,18 or Weyl semimetals 19 etc. In such systems, while a superconducting phase could be achieved, clear manifestation of topological superconductivity remained an unattained goal. Most recently, with the discovery of a type-II Dirac semimetallic phase on the dichalcogenide PdTe 2 , 20-22 where a superconducting phase is known to emerge naturally, 23,24 there have been wide speculation that this superconducting phase might eventually emerge as a topological superconductor. Owing to the existence of a topological phase along with superconductivity, it warrants a thorough investigation of the superconducting phase of PdTe 2 through high-resolution spectroscopic tools.In this Letter, we report scanning tunneling microscopy and spectroscopy results performed on high quality single crystals of PdTe 2 in ultra-high vacuum and sub-kelvin temperatures to spectroscopically probe the nature of superconductivity. Through systematic temperature and magnetic field dependent experiments we found that the superconducting phase in PdTe 2 , despite it's proximity to a topologically non-trivial Dirac semimetallic phase, is conventional in nature where the superconducting order parameter shows a temperature dependence consistent with the prediction of the theory of Bardeen, Cooper and Schriefer (BCS) for conventional superconductors. 25 High quality single crystals of PdTe 2 were grown by a melt growth method. The starting elements, Pd...

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