Supplementary material
Pulse Laser Deposition (PLD) has been proven to be an outstanding device to make a plethora of materials such as magnetic semiconductors, functional oxides, superconductors, etc. Therefore, the growth of Topological Insulator (TI) thin films by the same tool reinforces the ability to synthesize multilayered heterostructures of the aforesaid mentioned materials and explore the novel physics arising from the interface.
Mobility of the PLD deposited thin films do not cross the range of 20 – 35 cm/Vs and has been reported earlier in previous reports given in references 1–4 . We have included a comparative chart of mobility and carrier density in the table below. PLD technique is a highly non-equilibrium process as compared to other slow crystal growing or deposition techniques yielding disordered polycrystalline thin films with lesser mobility. Single crystals which yield high mobility on the other hand being an equilibrium growth technique is not suitable for device fabrication. Therefore transport in these films can be diffusive.
In the main paper we have presented an extensive account of low field MR behavior where we observed weak anti-localization (WAL) effect yielding reasonable phase coherence length (l ϕ
) and transport channel coefficient (α). We have also observed a linear MR (LMR) behavior in the high field regime. WAL captures the topological aspects of the surface states since back scattering is forbidden owing to the presence of topologically protected states. High mobility on the other hand is responsible for observation of Shubnikov–de Haas (ShdH) oscillations, whereas low mobility enhances the LMR effect
5
. Therefore, we can attribute the low mobility in our sample as a boon rather than an obstacle. We know that mobility is not a topologically protected quantity. So, the reduced mobility does not hinder the topological aspects of topological insulator materials. Mobility influences the mean free path (l e
), whereas it does not influence the phase coherence length (l ϕ
) which is a manifestation of topologically protected surface states.

Journal Material Growth
Procedure
Pulse Laser
Deposition
Electron concentration
1.3*10
14
cm
-2
(2D)
Molecular Beam
Epitaxy
5*10
19
cm
-3
Mobility
(cm 2 /V.s)
10 Applied Physics
Express 4(2011)
083001
Thin Solid Films
534 (2013) 659-
665
Thin Solid Films
520 (2012)
6459-6462
Appl. Phys. Lett.
101, 202403
(2012)
Appl. Phys. Lett.
102, 012102
(2013)
Appl. Phys. Lett.
100, 032105
Our work
Bi
2
Se
3
Bi
2
Se
3
Bi
2
Te
3
Bi
2
Te
3
Bi
2
Te
2
Se
Bi
2
Se
3
Bi
2
Se
2
Te
Pulse Laser
Deposition
Pulse Laser
Deposition
Pulse Laser
Deposition
2.75*10
19
1.07*10
2*10 19
20
cm
cm
cm -3
-3
-3
43.2
Not mentioned
Not mentioned
100
Molecular beam
Epitaxy
Pulse Laser
Deposition
~2*10
19
cm
-3
9*10
19
cm
-3
Not mentioned
20
Table 1 Comparative values of carrier density and mobility from previously published papers alongside our current manuscript. Note that the first row gives the 2D carrier density in terms of cm -2 and appears to be less.
References
1. Le, P. H., Wu, K. H., Luo, C. W. & Leu, J. Growth and characterization of topological insulator Bi
2
Se
3
thin films on SrTiO3 using pulsed laser deposition. Thin Solid Films 534,
659–665 (2013).
2. Onose, Y. et al.
Pulsed Laser Deposition and Ionic Liquid Gate Control of Epitaxial Bi
2
Se
3
Thin Films. Appl. Phys. Express 4, 083001 (2011).
3. Zhang, S. X. et al.
Epitaxial thin films of topological insulator Bi2Te3 with two-dimensional weak anti-localization effect grown by pulsed laser deposition. Thin Solid Films 520, 6459–
6462 (2012).
4. Zhang, H. B., Yu, H. L. & Yang, G. W. Experimental evidence of the nanoscaled topological metallic surface state of Bi
2
Te
3
and Sb
2
Te
3
films. EPL (Europhysics Lett.
95, 56002
(2011).
5. Veldhorst, M. Snelder. et al. Magnetotransport and induced superconductivity in Bi based threedimensional topological insulators. Phys. Status Solidi RRL 7, No. 1-2, 26-38(2013)