Unable to createIndex on model. key must not contain '.'

For example I have the vehicles collection with items as the example below:

{
"_id" : ObjectId("58d7f5a8e0661b63f05f690c"),
"imei" : "000000000000001",
"customerId" : ObjectId("58d7f48be0661b63f05f4a25"),
"gsmNo" : "0000000002",
"licensePlate" : "X-8830-34",
"audit" :
{ "updatedAt" : ISODate("2011-05-22T08:20:02.000Z"), "deletedAt" : ISODate("2010-08-26T08:31:59.000Z") },
"accessControl" :
{ "get" : [ ObjectId("58d7f47ee0661b63f05f0836"), ObjectId("58d7f47ee0661b63f05f0837") ], "patch" : [ ObjectId("58d7f480e0661b63f05f0867"), ObjectId("58d7f47ee0661b63f05f07c3") ], "put" : [ ObjectId("58d7f47ee0661b63f05f07c3"), ObjectId("58d7f47ee0661b63f05f07c5") ], "update" : [ ObjectId("58d7f47ee0661b63f05f07c3"), ObjectId("58d7f47ee0661b63f05f07c5"), ObjectId("58d7f47ee0661b63f05f07ca"), ObjectId("58d7f47ee0661b63f05f07cb"), ObjectId("58d7f47ee0661b63f05f07cc") ], "delete" : [ ObjectId("58d7f47ee0661b63f05f07c3"), ObjectId("58d7f47ee0661b63f05f07c5") ] }
}

Trying to create an index via

db.collection.createIndex({'accessControl.get': 1}, {background: true}, cb);

results in error:

key accessControl.get must not contain '.'